CHAPTER TWO
The Tipping Point
THE FIRST SEVEN WEEKS, 6 JUNE–25 JULY 1944
The Strategic Aim
After much wrangling between the British and the Americans, the Combined Chiefs of Staff (CCS) agreed on a directive that was issued to the Supreme Commander, AEF, on 12 February 1944. General Eisenhower was told: “You will enter the Continent of Europe and, in conjunction with the other Allied Nations, undertake operations aimed at the heart of Germany and the destruction of her Armed Forces.” Eisenhower clarified this mission by stating that “the purpose of destroying enemy forces was always our guiding principle; geographical points were considered only in relation to their importance to the enemy in the conduct of his operations or to us as centers of supply and communications in proceeding to the destruction of enemy armies and air forces.”1 The Germans’ centre of gravity, the seizure or destruction of which would end their ability and will to fight, was thus assessed as being their armed forces rather than the national capital or areas of economic importance. Straightforward as this aim may have been, there was much disagreement over how and where it should be accomplished, and at times, it seemed as if it had been lost to sight. The operational-strategic path that would lead to the enemy’s destruction was far from clear when the invasion forces were still building up in England. First, the Allies had to establish a firm bridgehead in France, a sine qua non that was expected to be very difficult, with no certainty of success.
Establishing a Lodgment: Successes and Disappointments
On 15 May 1944 General Sir Bernard Montgomery, the interim Allied land forces commander in chief (C-in-C), had outlined his “master plan,” the concept of operations for Operation Overlord, to Eisenhower; the principal land, sea, and air component commanders of the AEF; and some of the political leaders who would oversee and execute the invasion.2 Following the achievement of air superiority, the isolation of the invasion area by air interdiction, and the fixing of German forces in the Pas de Calais by deception (Operation Fortitude), the Normandy campaign would evolve in three broad phases. The projected progress of the invasion is shown in map 2.1.
In the first phase, the Allies would establish a substantial bridgehead. They would land on an 80 km (50 mile) frontage with Lieutenant General Sir Miles Dempsey’s Second British Army to the east and Lieutenant General Omar N. Bradley’s First US Army to the west. By about D+15, the Americans would have taken Cherbourg, an indispensable deep-water port. By D+20, it was envisaged that the Allies would have advanced to a line about 50 to 60 km (30 to 40 miles) inland and 150 km (90 miles) long, running roughly from Avranches on the Atlantic coast to Domfront and Falaise and then to Cabourg on the Channel coast. This would create a bridgehead with sufficient depth and maneuver room to be defensible and sizable enough to allow for the transfer of substantial forces and their necessary administrative support from the United Kingdom. It would also provide the airfield sites (especially on the Caen-Falaise plain) required by the air forces to support and defend the ground troops effectively: as long as fighter-bombers had to traverse the Channel at its widest, their response and loiter times would be unsatisfactory, as would be their depth of penetration into the enemy rear areas.
Before the start of phase two, there might be an operational pause to allow for the buildup of combat power and logistic resources to enable offensive operations to continue; ideally, however, the development of operations would be seamless. The British would push eastward and southeastward to the river Touques and Argentan, fixing the main enemy forces by aggressive action and shielding the Americans’ left flank while they drove south to the Loire and cut off Brittany from the hinterland. Then the newly introduced Third US Army under Lieutenant General George S. Patton would clear the Brittany peninsula and thereby secure the ports deemed essential by SHAEF logisticians to allow fresh formations and supplies to flow into the theatre directly from the United States.
In the final phase the whole Overlord lodgment area—as far west as Brest, as far south as the Loire, and as far east as the Seine—would be occupied by around D+90. With that achieved, the Normandy campaign would be over, and the Allies would concentrate overwhelming strength for the power drive that, starting around D+120, would carry them into the heart of Germany. The main effort would focus on the Ruhr industrial area.3 The enemy would endeavor to retain this most important centre of war-related production and, in doing so, would be brought to battle and destroyed. By which armies, where, and how this would be accomplished would be determined when the operational situation was clarified.
Thanks to the Fortitude deception plan, the defenses on Normandy’s shores were far less developed and dense than those in the Pas de Calais; moreover, the landings on 6 June achieved both operational and tactical surprise. Furthermore, the German High Command (Oberkommando der Wehrmacht [OKW]) suspected that the assault against Normandy was a feint to lure forces away from Fifteenth Army, which was defending against the real main effort expected to come against the Pas de Calais. Accordingly, it was slow to release the reserves that might have defeated the invasion, especially if aided by a period of bad weather, before the Allied buildup became too strong to overcome. In the first week alone, the Allies landed 326,000 men and more than 2,000 tanks. This was, in fact, a rate of reinforcement that the Germans, given the limitations of rail and road transport capacity and the Allied air interdiction effort, would have been hard-pressed to match.
By 13 June, a continuous if shallow bridgehead had been established. However, progress had fallen short of Allied hopes. On the left, the British had failed to take Caen, a vital road centre with crossings over the river Orne to the south that had been unrealistically designated as a D-Day objective. Their foothold over the river to the east was very restricted. The enemy thus enjoyed an uncomfortably generous view of a critical part of the British sector, denying them the space to build up necessary forces and administrative areas and to establish airfields. The danger remained of a German counterattack to roll up the bridgehead from the east. The problem at Caen was to determine the operations of Dempsey’s Second Army for the next few weeks. In the west, the Americans were still more than 20 km (12 miles) from Cherbourg and somewhat less distant from the key junction of seven roads at St. Lô, significantly short of the expected rate of advance. First Army and the right wing of Second Army had encountered a complication for which they were unprepared. Very soon after landing, they found themselves moving into the bocage.4 Although the Allies had an abundance of preinvasion air and ground photography and excellent maps of Normandy, for some reason, the military implications of this difficult, defensible terrain had not sunk in. The ground, skillfully exploited by a determined enemy, prevented the advance from gaining momentum.5
Montgomery had always accepted that the preponderance of German combat power was likely to be committed against Second Army. Simple geography placed it on the more threatening and, at the same time, more accessible axis (the shortest and easiest route to Paris and thence Germany). Faced with an initial and important failure at Caen, he developed his operational idea to meet the unwelcome circumstances (though maintaining, in the face of evidence to the contrary, that all was going according to his master plan). The British would mount a series of attacks with two aims in mind. The first was to take Caen and gain a favorable line from which decisive operations could be launched when the time was right. The other, more important one was to attract as much German strength as possible into Panzer Group West, facing Second Army, and fix it: this would enable Bradley’s First Army to advance more rapidly against the German Seventh Army to seize Cherbourg and, having done so, break out in the west, thus paving the way for Third Army’s thrusts into Brittany and eastward.
OKW remained concerned until the end of July that the main invasion would come in north of the Seine, mounted by the mythical First US Army Group (FUSAG). Accordingly, it kept its Fifteenth Army strong.6 However, forces in Brittany, the southwest and south of France, and Scandinavia were depleted to reinforce Normandy, and the strong II SS Panzer Corps was sent back from the Russian front.7 These reinforcements were not enough to recover the initiative or seriously threaten the viability of the lodgment, but they were sufficient to, in Montgomery’s words, “rope off ” the invasion force and create what looked like a stalemate. Until July was all but over, attritional battles like those of the First World War, with casualty rates reminiscent of the Somme and Third Ypres, remained the norm.8 By 25 July, the Americans had lost more than 70,000 men, and the Anglo-Canadians more than 46,000 (excluding battle exhaustion cases). The pace of the advance was painfully slow. Anglo-Canadian troops finally took the southern suburbs of Caen on 20 July (D+43), and they were still almost 25 km (15 miles) north of Falaise, a D+17–20 objective. Cherbourg fell to the Americans on 26 June (D+19) but was unusable until September, and when they at last captured St. Lô on 19 July, they remained more than 30 km (18 miles) from their intended D+17 line Granville-Vire.
The slowness of the advance and its rising casualty toll gave rise to dissatisfaction and dissension within the Allied ranks. American soldiers, encouraged by a press that was every bit as chauvinistic as the British, decided that their ally was not pulling its weight and not taking its fair share of the pain.9 A scapegoat was sought by some, and thanks to his arrogance, insensitivity, and apparent assumption of infallibility, Montgomery was a popular choice. Most American generals, including Bradley and Patton, had heartily disliked him since the previous spring for his patronizing attitude toward the US Army and his disregard for its needs and interests. Many senior airmen, including the Deputy Supreme Commander, Air Chief Marshal (ACM) Sir Arthur Tedder, also harbored grudges that were now reinforced by Montgomery’s failure to provide much-needed airfield sites. Senior officers (including British ones) at SHAEF were anxious to see him sacked by the Supreme Commander. Discontent spread as far as Prime Minister Winston Churchill and the US Chief of Staff of the Army, George C. Marshall. What many perceived, with little justice, as the repeated failures of the land forces commander culminated in Operation Goodwood, which ground to an expensive and ignominious halt on 20 July. Montgomery was thought to be overcautious, and this, combined with his irritating insistence that all was proceeding without a hitch according to his master plan, sharpened existing enmities. There were, however, other reasons for the lack of progress. Both Allied armies suffered from deficiencies in doctrine and training, exacerbated in some areas by equipment that was inferior to the enemy’s. Only painfully acquired experience would enable them to rectify these weaknesses and capitalize fully on their strengths, including particularly a growing superiority in men and materiel, to defeat their highly capable enemy.
THE LAND SITUATION ON THE EVE OF THE BREAKOUT
Not that he had received much recognition, far less thanks, for it, but General Montgomery’s operational idea had, by 25 July, created the conditions for a transition to more decisive operations than had been possible in the buildup phase of Overlord. For a start, both armies had fought their way through to acceptable lines of departure from which such operations could—at least in theory—be mounted.10 And the inexorable agglomeration of Allied fighting power had created the numerical superiority to do so. Moreover, British efforts to attract the bulk of German armor onto the eastern flank and thus enable an American breakthrough in the west had borne fruit (at the cost of casualties and the frustration of their own plans).
The Correlation of Forces on 25 July
With the disembarkation of 5 US Armored Division on 25 July, the Allies had assembled thirty-three divisions in Normandy—eighteen of them American, and fifteen British and Canadian.11 They were opposed by twenty-four German divisions and some parts of divisions (excluding troops still tied down in static coast defense). Some authors have used this 1.4:1 correlation of formations to suggest that the Allies did not enjoy a substantial numerical advantage. However, this ignores two factors in particular: most German divisions were substantially smaller than their Allied (especially British) counterparts, and many were understrength even before they suffered attritional losses that were not made good. The Allies also held a much greater proportion of their strength as corps- and army-level assets. The British had almost twice as many tanks in their eight independent armored brigades as they had in armored divisions, and about one-third of their artillery was found in Army Groups, Royal Artillery (AGRAs) at the higher formation level; about half of US field artillery and tanks and tank destroyers were found in nondivisional organizations. By contrast, less than 9 percent of German armor, 11 percent of German artillery (i.e., guns and howitzers), and 23 percent of manpower (including only 16 percent employed in service support tasks) were found in GHQ units. Nor does the fact that the Germans had a lower proportion of their men employed in combat and service support roles indicate greater fighting power; German infantrymen would become acutely aware of their inferior artillery and logistic support.
In all, by 25 July, the Allies had deployed 1,452,000 soldiers—812,000 American and 640,000 British and Canadian;12 6,757 tanks and tank destroyers—3,371 American and 3,386 British-Canadian (excluding replacements for about 2,100 already lost); and 3,240 artillery pieces—1,720 American and 1,520 British-Canadian. The Germans had committed about 490,000 men to Normandy but had taken almost 117,000 casualties and received only 10,078 replacements; their strength by 25 July was therefore approximately 380,000. They had sent 1,869 tanks, assault guns, and self-propelled (SP) antitank guns (including replacements) but had written off about 450 (and another 450 or so were in workshops). They had also sent 1,672 artillery pieces; the number lost is unknown, but the figure was probably considerable. It is noteworthy that, despite this wasting of strength on the invasion front, Normandy continued to be starved of the troops needed to hold the German line. There were twenty-four divisions (most of them tired) or parts of divisions in Normandy, eighteen between the Seine and Amsterdam awaiting a second cross-Channel assault, and eleven elsewhere in France (another invasion, in the south of France, was expected imminently). The seriousness of the German maldeployment is well illustrated by the fact that in Normandy, the only active front in the west, the Allies enjoyed a 3.8:1 superiority in manpower, 4.7:1 in armor, and about 3:1 in artillery. The last figure is seriously misleading, however, as German ammunition supply was woefully inadequate; American guns, for instance, were firing four times as many shells per day.
Force ratios are important, but they do not tell the whole story when assessing relative strength. Qualitative factors can be very significant too. Several historians have explained the initially slow progress of the Allied armies in Normandy, especially the British, by reference to German technological superiority in combination with terrain that was ideal for defense. This contention deserves some consideration.
Infantry. British small arms were more suited to colonial combat, the army’s accustomed milieu, than to modern continental warfare. The infantryman’s rifle was still, essentially, the bolt-action weapon first used in the Boer War at the turn of the century. It was supplemented by two submachine guns (SMGs): the heavy American Thompson, and the world’s cheapest, nastiest, and most unreliable, the Sten. The US infantry fared better, as its basic weapon was the excellent Garand automatic rifle; its high rate of fire (thirty rounds per minute) persuaded the army, somewhat dubiously, as it transpired, that it needed fewer machine guns. Those Americans whose primary job was not shooting with a personal weapon carried a carbine or SMG. The Germans had a bewildering variety of weapons, including vast arrays of captured ones of differing calibers and reliability. Most riflemen carried bolt-action rifles, while a fair proportion of the men in more favored or simply luckier units carried semiautomatic rifles or machine pistols. However, personal weapons are considerably less important than crew-served ones in deciding combat outcomes—a fact the Germans took to its logical conclusion by turning most riflemen into little more than ammunition carriers for the machine guns. These plentiful and frightening German machine guns had an adverse effect on the morale of British and American infantry, as evidenced by every infantryman’s account of the campaign. They also had much to do with the Allies’ reluctance to advance without plentiful artillery support.
Most German infantry battalions had eight to twelve 81mm mortars and between forty-three and sixty-three general-purpose machine guns (MG-34/42). Both British and US battalions had six such mortars, comparable in range and bomb weight; an American battalion also possessed nine company-level 60mm mortars, and a British battalion had seventeen platoon-level 2 inch (50mm) mortars. A British battalion had forty-one Bren light machine guns (LMGs), and an American battalion had forty-five Browning automatic rifles (BARs); the US battalion also had twenty .30 caliber and six .50 caliber machine guns.13 The rate of fire of the belt-fed MG-34/42 was roughly double that of Allied machine guns (and treble that of the BAR). The Germans could thus generally generate higher volumes of fire at unit level, especially compared with the British; but this was also true of the semiautomatic Garand rifle on which the US infantry relied as a substitute for machine guns. Some Wehrmacht divisions also fielded varying numbers of heavy machine guns and mortars (105mm and 120mm) and short-range infantry guns (75mm and 150mm, usually used over open sights) in support units to augment the firepower of battalions. Of course, Allied formations did likewise, albeit less generously. The British infantry division’s machine gun battalion, for instance, was a formidable asset with its thirty-six Vickers medium machine guns and sixteen 4.2 inch (105mm) mortars. The US Army infantry division’s chemical mortar battalion fielded thirty-six 4.2 inch mortars.
On the defensive, even a few MG-34/42s surviving an artillery preparation or barrage were capable of bringing attacking infantry to a juddering halt, pinning the riflemen, with their inadequate (as they perceived them) LMGs and BARs, to the ground. Sometimes, a flurry of mortar bombs inflicted casualties and disorganization in the forming-up place before the attack had even begun. Often, the advance was halted in an area already registered as a target (a preselected killing zone) by the defender’s mortars, which then worked over the unfortunate would-be attackers. And, of course, the Germans immediately subjected their defensive positions, once captured by the enemy, to intense, accurate fire before consolidation could take place. The mortar and its artillery cousin, the nebelwerfer multibarreled rocket projector, were the most effective infantry killers in Normandy. A 30 July report by the British No. 2 Operational Research Section (ORS) showed that over 70 percent of British casualties were caused by these weapons. Until both infantry and, more importantly, combined-arms tactics matured from the rather simplistic methods of the early days, attacks would too often prove expensive failures.
Armor. The Sherman, in one of its various marks, accounted for two-thirds of the Allied medium tanks in Normandy.14 Both it and the British Cromwell, which made up another 20 percent, were seriously underarmored. The vast majority of German 75mm tank and antitank guns could penetrate any aspect of their armor out to about 1,500 m (1,640 yards), and the Panther long-barreled 75mm and Tiger 88mm guns even further (although engagements over 1,000 m were rare). Moreover, the Sherman had a distressing tendency to burst into flames when penetrated (in 73 percent of cases, according to operational analysis).15 They were also undergunned, at least for combating enemy tanks. (In the American view, the purpose of tanks was not to fight other tanks but to support infantry and exploit success.) Their 75mm medium-velocity (MV) guns could defeat the strongest protection of most German armored fighting vehicles (AFVs) out to over 1,000 m, but they were effective against the Panther at only half that distance or less and against the Tiger at point-blank range, if at all. The only really effective tank gun was the 17-pounder on the British “Firefly” variant. This could knock out the best German tanks at over 1,000 m. The Sherman had its virtues, though. It enjoyed a good range of action—about 200 km (125 miles); it was maneuverable; its high-explosive (HE) performance was good (the reason for choosing an MV gun); and, above all, it was mechanically reliable, ensuring high levels of availability.
While most British independent tank brigades were equipped with Shermans, three had Churchill infantry tanks. These were armed with the same 75mm MV gun but were thickly armored to enable them to close onto defensive positions with the infantry they supported. They could withstand hits by the standard German 75mm at ranges over 500 m, but both Panthers and Tigers (and 88mm antitank guns) could kill them out to 1,500 m. The Churchill was excellent across difficult terrain, but it was slow, as befitted its role.
The last major category of Allied AFVs was the tank destroyer. These vehicles were the product of a flawed American doctrine. They were intended to be massed and used as a mobile reserve to defeat attacks by concentrated armor. Enemy tanks were supposed to be stalked and destroyed by these SP antitank guns, so the M-10 and M-18 were very mobile but even more lightly armored than the Sherman, whose chassis they shared; however, they had somewhat more effective antitank guns (the 3 inch and 76mm, respectively).16 Although they could penetrate most enemy armor out to well over 1,500 m, these guns would defeat a Panther only at about 700 m and a Tiger at 500. The British began to rearm their tank destroyers with the 17-pounder, but only about 100 saw service in Normandy.
Clearly, German units equipped with Panthers and Tigers enjoyed a significant combat advantage, provided, of course, they managed to reach the battlefield. The Tiger had less than half the range of the Panther or of Allied tanks, and both were mechanically unreliable; the Tiger, in particular, spent a significant amount of time in workshops.17 And only 650 Panthers and 138 Tigers saw service in Normandy (along with 25 Panther-based SP antitank systems). The vast majority of the 2,248 AFVs present at one time or another (including replacements) were Mark IV panzers (900), roughly equal to the Sherman; turretless StuG III assault guns (550), inferior to the Sherman; or one of the other 200 assault or SP antitank guns (mostly inferior) that were around in small numbers. In all, the Allies committed about 6,300 tanks and tank destroyers (excluding 2,300 light tanks and all replacement tanks): 2,600 US and 1,820 British Shermans (the latter including 420 Fireflies), 570 Churchills, 340 Cromwells, and 756 American and about 200 British M-10s (including more than 100 armed with the 17-pounder). This means that about one-third of German AFVs were superior to their Allied counterparts, and roughly the same proportion were inferior. Or, to put it another way, for every eight Allied AFVs, there was one better-armed and better- armored German one.18
Of course, because the Allies were mostly on the offensive, they had to fear German antitank guns as well as armor. Most (but far from all) divisions had twelve to twenty-four 75mm or 88mm guns, some had eight to twelve 88mm flak and/or 88mm guns in the artillery regiment, and many infantry divisions possessed up to thirty-six panzerschreck (manpack 88mm antitank rocket launchers); the infantry was also plentifully supplied with the panzerfaust (a one-shot antitank grenade launcher).19 In addition, five GHQ antitank battalions had another 138 75mm or 88 mm guns. It appears, however, that towed guns, perhaps because of their vulnerability to artillery and tank HE rounds, were much less effective than armor as tank killers. Based on admittedly incomplete and possibly unreliable evidence, it appears that, in Normandy, they accounted for about 25 to 30 percent of Allied tank kills; close combat (presumably mainly with panzerfaust and panzerschreck) accounted for almost as many, and the rest were attributable to AFVs. The Allies, particularly the British with their 17-pounders and APDS ammunition for their 6-pounder (57mm) antitank guns, were at least as well prepared as the Germans to repel armored attacks.
Most British sources stress the presence, in their sector, of the bulk of III Flak Corps, with its 108 to 116 88mm flak guns. However, it seems that these guns were used in the antitank role only in extremis (though they were sometimes used as conventional artillery because GHQ artillery was in short supply). Indeed, the cumbersome nature and great weight of the 88mm flak limited its mobility; its high silhouette rendered digging in and concealment difficult, and it was vulnerable to artillery and tank HE fire. These factors, and the lack of crew training for antitank combat, were good reasons to keep these weapons to the rear; a brief experiment in the use of eight 88mm flak guns in flakkampfgruppen (antitank groups) was not considered a success. Moreover, the Germans needed all the air defense they could muster, given the omnipresence of Allied bombers and fighter-bombers. The corps itself claimed only ninety-two tank kills, twelve of them with the panzerfaust (out of a total army-SS claim of 3,663 destroyed tanks).20
Among the British AFVs were the “funnies” of 79 Armored Division. Sherman “Crab” tanks opened paths through minefields relatively rapidly and under armored protection, doing away with the need for slow hand clearing by vulnerable sappers on foot. The Churchill “Crocodile” mounted a flamethrower as well as main armament and greatly eased and expedited the business of house and hedgerow clearing by the infantry; the defense frequently folded when these vehicles put in an appearance. The Churchill AVRE (engineer tank) carried a fascine or short bridge for ditch crossing and was armed with a demolition gun whose massive charge was very effective against houses, concrete emplacements, and other fortified positions. These specialist vehicles added considerably more combat value to combined-arms teams than their numbers would suggest. Many Anglo-Canadian units had good reason to be grateful to Montgomery for his farsightedness in backing their development and production; by the same token, American units could be forgiven for deploring their rejection by Bradley.
Having looked at the overall balance of armor and put the German qualitative advantage in perspective, it is necessary to note the profound sectoral imbalance by late July. The success of Montgomery’s operational idea resulted, on the eve of the American breakthrough, in First Army facing only two panzer and one panzer grenadier divisions with around 200 tanks and SP guns (excluding those in workshops). The Second and newly activated First Canadian Armies had seven panzer divisions on their front and the three heavy panzer (Tiger) battalions, for a total of more than 600 operational AFVs. In fixing the preponderance of German armored strength, British and Canadian soldiers paid a heavy price to set the conditions for American success in Operation Cobra.
Artillery. Earlier in the war, the Wehrmacht had relied heavily on air-delivered firepower rather than artillery, and priority was given to the production of AFVs over guns. By the time it was losing air superiority, the priority in artillery production had shifted to flak to protect the homeland from increasingly devastating attacks in the combined bomber offensive; by June 1944, there were no fewer than 55,000 antiaircraft guns in service. Despite this relative neglect of the field artillery branch, the Germans deployed a considerable quantity in Normandy. It did not, however, make a commensurate contribution to the defense. This was not, for the most part, a reflection on the quality of the weaponry. The Germans’ field and medium (mostly 105mm and 150mm) guns and howitzers were roughly comparable to their American equivalents, and the 105mm was almost half as powerful again as the standard British divisional fieldpiece.21 The Allies, however, possessed much larger quantities of medium and heavy artillery with a good combination of reach and punch. Unfortunately for German gunners, a significant proportion of their pieces were of foreign, captured stock—Soviet, Czechoslovak, French, and Italian. Apart from the Soviet weapons, these were generally inferior to German-made guns; more important, ammunition resupply rapidly became intermittent, problematic, or downright impossible, and even German shells became increasingly hard to come by. The maldistribution of dumps, a growing shortage of trucks and their inability to move by daylight in clear weather, as well as the multiplicity of ammunition natures (types) required all conspired with potent Allied counterbombardment to severely limit the effectiveness of German artillery. For every four American shells fired, the Germans replied with one at best. Nor could the Germans make optimal use of radio communications, which were technically excellent but woefully inadequate in quantity.
A hangover from the days of blitzkrieg, when air largely substituted for corps artillery, the vast preponderance of German artillery was found at the divisional level. Only about 180 guns and howitzers were present in the fifteen GHQ artillery battalions (which were not organized in larger units and included a mere 19 long-range, comparatively heavy 170mm guns). By contrast, taking the entire summer-autumn campaign into account, over one-third of Anglo-Canadian artillery (544 guns) was found in the corps-level AGRAs, typically around 64 medium and heavy guns in each, and over half of all US field artillery (about 1,440 weapons) was found in nondivisional units.22 The Allies also increased their artillery strength considerably by reassigning heavy antiaircraft units to the ground role once the German air threat diminished. Moreover, each ally had worked out a very effective, flexible command and control system that the Germans, despite recognizing its advantages, could never even begin to match for want of materiel. Command of artillery was focused at the corps level, but control was decentralized to the lowest possible level. For instance, a British forward observation officer (FOO), usually a captain, was empowered to call down the fire of an entire divisional artillery regiment consisting of 72 25-pounders on an “Uncle” target of his own choosing. He could even direct his entire corps as well as divisional artillery (at least every gun in range) onto a “Victor” target. The time between the FOO’s fire order and the arrival of the shells was normally about five minutes for an Uncle (divisional) target and as little as eight minutes for a Victor (corps) target.23 Furthermore, fire could be arranged “time on target” (TOT), so that the first round from each gun arrived at the same instant, maximizing effect through a combination of surprise and concentration. Accurate survey and meteorology updates every six hours, together with periodic calibration, also improved the prospects of a first-round hit. The Germans could not match such accomplishments.
It is difficult to overstate the importance of these developments, given that the artillery was the most effective part of both Allies’ combat arms and had to make up for some deficiencies in the others. In the attack, the ability to produce quick fire plans to maneuver massed fire around the battlefield at short notice often mitigated unexpected problems that threatened to hold up the advance. Just as important was the gunners’ ability to break up attacks and counterattacks even before they could close with the defenders; many a precarious gain was held thanks to defensive fire tasks arranged to meet the inevitable counterattack. Only rarely did the enemy manage to defeat attacks with his artillery defensive fire, due in part to the Germans’ problem with ammunition supply. More often, though, the enemy’s failure was the result of Allied counterbombardment measures. Benefiting from good air photography, sound ranging, and other techniques and, above all, from air observation posts in good weather, the Allies could usually locate enemy batteries quite quickly, and plentiful medium and heavy artillery, not to mention fighter ground attack, delivered crushing weights of fire. Usually, the appearance of a light aircraft in the sky was enough to cause nearby German batteries to fall prudently silent. Of course, the Germans did their best to minimize the effect of Allied superiority through the skillful use of camouflage and dispersion, roving tactics with their small numbers of SP guns, and the studied use of pauses in Allied fire to redeploy; they succeeded in keeping their casualties remarkably low, but at the price of being largely unable to influence the outcome of the battle.
As previously noted, German mortars and the 350-plus nebelwerfers (mostly six-barreled 150mm, with a fair number of five-barreled 210/300mm) were actually more troublesome than conventional artillery. They were short-ranged but light, small, and easily concealed and deployable on inaccessible reverse slopes due to their high-angle fire. The mortars possessed a high rate of fire, and a battery of nebelwerfers could deliver (albeit rather inaccurately) simultaneous salvos of thirty to thirty-six rounds; both were thus excellent weapons for “shoot and scoot” tactics to avoid counterfire. However, by August, the problem was being mastered. The British, for instance, had introduced a countermortar organization in each formation that linked target acquisition means (including, for the first time, radar) and a dedicated communications system linked to likewise dedicated fire units of heavy howitzers or mortars, medium artillery, or heavy antiaircraft artillery firing airbursts.24
Increasingly, Allied artillery dominated the battlefield. In set-piece battles, it was a battle winner. However, when operations became progressively more mobile and fluid in August and September, as the German defense collapsed, the gunners had problems keeping up with the rapid rate of advance. Towed, road-bound artillery cannot match the speed and flexibility of armor and mechanized or even motorized infantry; nor could its ammunition supply. Moreover, as commanders sought to meet the voracious demands for fuel created by pursuit, they were forced to leave most nondivisional assets behind as their transport was commandeered for logistic purposes. When pursuit ended and heavy fighting again became an issue, there would be an inevitable delay while the medium and heavy guns and their ammunition were brought forward.
Reflections on Allied Materiel Shortcomings
In view of the widespread concern expressed in both American and British infantry circles about their firepower deficiency in the face of the enemy’s numerous MG-34/42s and mortars, it is perhaps surprising that neither army saw fit to increase the number of Brens, BARs, and .30 caliber Brownings and mortars issued. Even if it were too great a challenge to double the number in each company, a firepower reserve of a platoon with half a dozen LMGs and another with light mortars, deployable to thicken the base of fire to support maneuver, would have lessened subunits’ dependency on support weapons and arms. As a self-help measure, some formations stripped out machine guns, bazookas, and mortars from noncombat units and used them to beef up the fighting infantry. In addition to taking the initiative and increasing their holdings unofficially, some units used captured German weapons for their own purposes (though this involved problems of ammunition supply and the danger that, given the distinctive sound signature of the German machine gun, they would be mistaken for the enemy). But that was hardly an excuse for official inaction.
The Americans and British both decided to stick with their older tank designs, despite their obvious inferiority as fighting machines, because they valued quick mass production. Within a fortnight of D-Day, concerns were being expressed at senior levels in 21 Army Group about the inferior firepower and protection of most British tanks (a postcampaign study revealed that German gunners required only 1.63 hits to knock out a Sherman, while it took 2.55 to deal with a Panther and 4.2 for a Tiger).25 General Montgomery’s response was to block the publication of “alarmist” reports, lest they damage morale, and to issue disingenuous reassurances. But facts that were self-evident to tank crewmen likely did the job of lowering morale well enough, without adding official blinkers. At least the War Cabinet decided, early in the year, to concentrate in the future on producing Fireflies, heavy Churchills, and eventually the excellent Comet.26 The Army Ground Forces (AGF) command in the United States, headed by Lieutenant General Leslie J. McNair, was just as disinclined as the British to acknowledge the immediate need for a better-gunned and better-armored tank. The excellent new M-26 Pershing was ready to go into series production in early 1944, but the AGF insisted on persevering with the Sherman (some with 76mm guns), and Pershings started to take the field only in February 1945. Nor did the army see fit to upgrade M-4s with the powerful 90mm gun, comparable to the Firefly’s 17-pounder.27 The AGF also continued to propound the discredited tank destroyer concept, and the upgunned (90mm) M-36 version was not provided in any quantity until the autumn of 1944.
When contemplating the British and American failure to respond to the problems posed by the enemy’s superior machine guns and tanks and numerous mortars, it must be remembered that these weapons were not encountered for the first time in Normandy. Experience in Tunisia, in Sicily, and on the Italian mainland should have given rise to a more timely response. The Germans managed it, after all. The Tiger and Panther tanks were both developed rapidly in response to the technological surprise achieved by the Soviets’ T-34 and KV-1.
The limitations of their weapons, combined with inadequate tactical doctrine and training, tended to discourage aggressiveness in Allied infantry and armored units. They preferred to rely on the excellent and abundant Allied artillery rather than their own firepower combined with maneuver to win ground. Although this certainly reduced casualties in individual tactical actions, it also meant that attacks were necessarily methodical and slow, too seldom achieving a rapid penetration by catching the enemy by surprise and thus off balance. The resultant gnawing through the defense prolonged battles and produced a steady drain of casualties. However, once the character of operations transitioned from attritional to maneuver, the high level of mechanical reliability of the Sherman and Cromwell tanks and their good road range enabled a sustained pursuit with a low dropout rate (as long as fuel resupply continued).
Mobility and Logistics
Never the mechanized juggernaut of legend, by late 1943, the Wehrmacht was well down the road of demotorization. Truck losses in North Africa, Italy, and, above all, Russia had reached critical dimensions. The decision was made to increase production to the maximum possible for 1944: 167,440 trucks. However, only 53,949 were manufactured in the first half of 1944, despite the fact that the bombing of relevant factories did not really start until the second half of the year. In all, 88,088 trucks were produced in 1944 (compared with 595,330 in the United States); these had to supply all fronts and the economy. As the loss rate of motor transport was considerably higher than the replacement rate—by a ratio of 3:1 between January and April—the situation continued to deteriorate. Moreover, the failure to produce sufficient spare parts resulted in high levels of nonavailability, as did fuel shortages.28 Many German quartermaster and repair elements also had to cope with the problems created by the use of captured vehicles of many nationalities for which spare parts were lacking, thus aggravating the issue of unreliability.
One consequence of this progressive demotorization was an almost total dependence on railways. Of course, rail was normally the fastest and most efficient method for moving formations or bulk goods over long distances without inflicting wear and tear on vehicles or exhausting the troops. Before the invasion, the Germans had been impressed by the extent (indeed, redundancy) of the French rail system and were not unduly worried about this reliance. However, they soon discovered that the rail net was much more vulnerable than the roads to disruption from the air, and the Allied air interdiction effort in France hugely reduced its capacity. The Germans found that they could not reinforce Normandy on the scale and at the speed required to win the race to build up superior forces and thus seize the initiative. When formations arrived, usually by a combination of road and rail movement, they did so in dribs and drabs, tired and late. Furthermore, prioritizing troop movements over resupply ensured that the defense would become crippled by ammunition and fuel shortages when the inadequate preinvasion stockpiles were used up. From mid-June, the Germans were living a hand-to-mouth existence with no reserves to cope with any surge in demand.
A low level of mobility characterized most German formations. The twenty-two static infantry divisions present in France and the Low Countries on D-Day were capable only of defending in place, unless and until they received transport. The other infantry divisions were reliant primarily or entirely on horse-drawn transport, although some had motor vehicles to haul their artillery or antitank guns and to provide for some of their logistic needs. Many possessed nowhere near their prescribed complement of about 4,600 horses. The infantry, of course, marched everywhere, save for the one battalion per formation that had bicycle mobility. In theory, armored formations were fully motorized. In practice, several of the ten panzer and one panzer grenadier divisions that served in Normandy suffered from severe deficiencies when the invasion started. Despite efforts to repair these, in mid-July more than half of them had only between one-third and two-thirds of their vehicular establishment. This limited their flexibility and tactical effectiveness.29
While the motor transport available to combat formations was inadequate, that devoted to their logistic support was derisory; for instance, the quartermaster general of Seventh Army had at his disposal a lift capacity of a mere 500 tons in early June. This was the inevitable result of giving priority to combat formations in the allocation of transport assets (a reflection of the traditional German tendency to exaggerate the importance of the fighting arms at the expense of their sustainability). The problem was worsened by the unanticipated need to switch considerable resupply efforts onto the roads when the railways failed to cope. This in turn drove up fuel consumption, aggravating the fuel shortage, and hastened the decline in vehicle numbers as breakdowns and accidents increased (only darkness and bad weather permitted driving on the roads without drawing the attention of Allied fighter-bombers). Vehicles were lost much faster than they could be replaced (4,200, including 1,866 trucks in Army Group B, in June alone). And the denuding of higher-formation transport pools became self-defeating as divisions were increasingly forced to use their own transport to fetch supplies from rear dumps rather than having them delivered forward.30
By contrast, the Allies enjoyed a high level of mobility. By 24 July, for instance, the Americans alone had delivered 56,468 wheeled vehicles to Normandy. Both US and British armored divisions were fully motorized or mechanized. Each infantry division, too, was highly motorized, although transporting all its infantrymen in one lift required temporary reinforcement by three truck companies from the plentiful pool held at higher levels; this was frequently done.
The Allied logistic system was as generous as the Germans’ was inadequate to support operations. To illustrate this, consider the divisional slice (a division’s manpower plus its proportionate share of corps, army, and theatre troops). An average US infantry division with normal combat attachments numbered 15,600 men; in addition, there were 14,958 corps and army troops (6,223 combat and 8,735 service troops) and 9,787 communications zone (COMZ) personnel—a divisional slice in July 1944 of 40,345. A British division had a similar slice (with about 8,000 vehicles, less than half of them organic to the division). In fact, the British army group had a bare majority of combat troops—56 percent—with 44 percent supporting them (even the infantry, at 14 percent of the total, was outnumbered by the Royal Army Service Corps’ 15 percent).31
The result of this asymmetric development of logistic capabilities would be disastrous for the Germans. When First Army launched Operation Cobra on 25 July, it did so with seven or more units of fire for all the important ammunition natures, barring only two. About 13 million gallons of fuel had been delivered into bulk storage, and decanting into jerry cans was taking place on the Continent.32 The German Seventh Army facing it was all but out of critical categories of ammunition (e.g., 88mm armor-piercing) and was down to 0.7 of a ration allotment of fuel.33 At the same time the Allies had attained a potentially decisive superiority in combat power, the German defense was culminating.
Command and Control
Tanks, mechanical transport, and aircraft were essential to restoring some sort of balance between firepower and mobility after the stalemate in the west during the First World War. At least as important in enabling armies to conduct maneuver warfare once again was the radio. As armies increased in size and were equipped with faster-firing, longer-ranged weaponry, firepower forced dispersion. Thus, Wellington’s army of almost 68,000 men had defended on a 3 km (2 mile) frontage at Waterloo; by 1944, that was the approximate doctrinal frontage of a single German infantry regiment, and such a unit would often be required to hold more than twice that. Whether in defense or, even more so, in attack, the successful command and control of modern forces could not be done with only messengers, visual signals, or inflexible and easily cut telephone lines. While line remained the preferred means of communication, especially in relatively static situations, efficient radios became the principal means as battles developed. Efficient is, of course, a relative term. In the days of vacuum tube technology and weak chemical batteries, radios were much more fragile and less reliable than they are today, and they had a very limited range. They were also bulky, heavy, and temperamental. Even so, those of 1944 were a far cry from the more or less immovable sets of the First World War, useful only at the level of high command. Vehicle-mounted radio sets (voice or Morse key) generally had a range of 16 to 24 km (10 to 15 miles), and there were manpack or at least man-portable radios (usually weighing about 15 to 20 kg [30 to 40 pounds]) with a range of up to 8 to 12 km (5 to 7 miles) for use at the battalion level and below.
Radios were essential if commanders wanted to keep abreast of the changing tactical and operational situation and direct their forces accordingly; the more dynamic and rapidly developing the battle, the more vital efficient communications became. Here again, the Allies enjoyed an advantage over their enemy. They provided radios in increasing numbers to lower and lower levels; in the US Army and often in the British and Canadian armies as well, they percolated down to even platoon level. This enabled intimate support from the artillery, often en masse, at all stages of combat. By late July, compatible sets were being placed in tanks to make tank-infantry cooperation more effective, and VHF sets were being fitted in tanks or other “contact cars” to enable forward air controllers to direct close air support onto targets very close to their own troops. The Germans, overstretched and short of resources, could not even replace losses, much less improve their radios or expand their distribution. This was a growing tactical handicap that precluded the sort of flexible and devastatingly effective maneuver of massed artillery fires that did so much to ensure Allied success.
At the end of the day, of course, command and control is about concepts, doctrine, and command philosophy. Arguably, the Germans were more in tune with the demands of the contemporary battlefield, and this helped them offset, to an extent, the Allies’ materiel advantages. For instance, German headquarters at each level of command were smaller, less bureaucratic, and therefore faster to act and react in fluid and fast-developing situations than their Allied equivalents.
The Land Situation: Conclusions
There is some truth to the contention that the German land forces possessed better weaponry—but only in some respects, and not at all in the crucial area of artillery. And although the Germans made excellent use of the terrain’s defense-enhancing characteristics, it is clear that the Allies were slow to adapt their operational concepts and tactics to overcome these German advantages. For too long, they were willing to play to the enemy’s strength. While the fighting in Normandy was restricted to an area in which the terrain was largely inimical to maneuver and the frontage was a mere 120 km (75 miles) or so, the Germans’ lack of mobility was a severe but not a critical limitation. They were able to impose a linear, attritional nature on combat—an approach that actually suited both American and British doctrine, with its emphasis on overwhelming firepower rather than maneuver. Of course, the Germans were bound to lose in an attritional struggle, given the Allies’ growing superiority in numbers and firepower (including air-delivered firepower); it merely took longer because the Allies were unable to maximize all their advantages. Once the Allies broke the quasi-stalemate (as happened after Operation Cobra) and the campaign entered a maneuver phase, the Wehrmacht’s inferior mobility and dire supply situation became campaign-losing handicaps. The Allies’ ability to outflank rapidly any effective defense and to outpace and cut off enemy forces attempting to withdraw made it possible to destroy whole formations.
AIRPOWER AND THE LAND CAMPAIGN
From Air Superiority to Air Supremacy
Air superiority is achieved when the degree of dominance is such that freedom of friendly air and related land and sea actions is assured at an acceptable cost while the enemy’s is drastically reduced. Ideally, achievement of superiority is followed by air supremacy, which renders the enemy air force incapable of any effective interference. Winning air superiority was the priority of the Allied air forces and a prerequisite for their other missions and for the success of the invasion. It was essentially a business of attrition, and there were two traditional approaches. Local, possibly only temporary, air superiority could be achieved by winning a succession of aerial combat encounters, forcing the enemy to abandon operations; this was how the RAF won the Battle of Britain. Regional superiority could be established through an offensive countercampaign aimed not only at winning air battles but also at systematically and progressively destroying the enemy’s air infrastructure (runways, fuel and ammunition supplies, maintenance facilities, and command and control systems, as well as aircraft on the ground). If these tasks could be accomplished over a sufficiently wide region, the enemy air force could be prevented from interfering with sea and land operations in a chosen area within it; this was how the Allies prepared for the 1943 invasion of Sicily and the subsequent campaign there and in Italy.
The Allies agreed on a far more ambitious approach at their Trident conference in May 1943. Subsequently christened Operation Pointblank, their combined bomber offensive had as its principal objective no less than the destruction of the Luftwaffe, primarily by smashing fighter-producing factories, repair shops, ball-bearing plants, and other essential facilities; there would also be airfield and depot attacks, especially within Germany, and, of course, aerial combat throughout the enemy’s depth as the Germans responded to attacks on critical targets.34 Continent-wide air superiority would enable the Allied air forces to go about the business nearest to their hearts: destroying all German war-related production and the morale of the civil population. And, particularly important as far as the CCS was concerned, Pointblank was an essential prelude to Operation Overlord.
The offensive against the German aircraft industry failed to prevent an increase in the number of fighters produced, a fact unappreciated by overly optimistic intelligence assessments. But the Luftwaffe was unable to translate this overall increase into a growth in front-line strength. Losses on all fronts (taken together) modestly outweighed gains. More important, aircrew casualties, combined with shortsighted training policies, meant that there were insufficient replacements, and their quality declined markedly (in mid-1944 Allied pilots received three to four times the 100 training hours of German pilots). In the first half of 1944 the Luftwaffe lost 9,648 aircraft, 6,648 of them while defending the west and the Reich itself. This, of course, reduced the Luftwaffe’s effectiveness and led to increasingly one-sided aerial battles and a fast-growing casualty bill—a vicious circle that got worse over time. Meanwhile, the Allies had geared up for a long war and were producing better aircraft at a much faster rate than their losses; they enjoyed a superfluity of aircrews as well.35
The Allies expected the Germans to react to the invasion by conserving their forces out of reach of tactical airpower until the landings took place. Then they were expected to pour squadrons into air bases within easy reach of the chosen sector and contest local air superiority, with all the advantages deriving from proximity; meanwhile, the Allied fighters would have limited loiter time as a result of having to fly from bases in faraway England. This approach was countered first by the Pointblank assaults, which kept the German fighter force fully stretched defending vital assets. Second, there was an offensive counter–air effort to establish regional as well as general air superiority by eliminating the Luftwaffe’s positional advantage. Thirty-four out of fifty major operational air bases and associated satellite airfields within 210 km (130 miles) of the invasion beaches were subjected to attacks that left their radar, communications, maintenance, and storage facilities and operating surfaces incapable of supporting normal operations. After the landings the campaign was stepped up, and all airfields within reach were similarly wrecked, with severe effects on serviceability and sortie rates. Lack of sufficient usable bases combined with continued, increasingly effective air attacks on Germany to pin and destroy Reich air defense fighters and with the disruption of rail transport required to equip and supply bases prevented the Germans from carrying out an effective surge to combat the invasion.
At the time of the invasion, the correlation of air forces was overwhelmingly in the Allies’ favor. Together, in combat squadrons in the United Kingdom, they fielded 3,467 heavy bombers, 1,545 light and medium bombers, 5,409 fighters and fighter-bombers, and 2,316 troop carriers and transports.36 To oppose them, the Luftwaffe’s strength in all of France and in the Low Countries amounted to 325 medium bombers (with undertrained crews), 75 ground attack aircraft, 325 fighters (170 of them single-engined), and 95 reconnaissance machines; serviceability rates were low. To reinforce this meager array, the Germans managed to find another 300 fighters and 135 bombers to provide about 1,000 aircraft of all types actually opposing the Overlord forces in the crucial first week. This was clearly inadequate to meet the weight of the Allied onslaught, and from the very beginning the Luftwaffe was on the defensive; indeed, it was soon struggling to remain in existence, never mind aiding the hard-pressed ground forces. In addition to repeatedly bombing air bases that showed signs of repair, the Allies maintained standing patrols over those bases closest to the bridgehead to prevent them from generating sorties. The defenders were forced to operate out of bases in the Paris area and even further back. Even their reconnaissance efforts became sporadic, and concerted fighter or bomber operations virtually ceased. Apart from tip-and-run raids and the harassment of Allied artillery spotters, the Luftwaffe’s efforts to combat the invasion were reduced to night bombing from high altitude (to avoid dense flak concentrations) and then, starting on 12 June, aerial mine laying; the former did negligible damage, and the latter caused only some relatively minor difficulties and delays.37
As June gave way to July, Allied air superiority transitioned to air supremacy. German antishipping forces, having accomplished very little, were withdrawn and then disbanded. Fighter units were hollowed out by mounting casualties and declining serviceability. They were unable to give top cover or air support to the army, even when it was vitally needed to avert the collapse of the front. By early August, the Allied attacks on the oil industry, begun in mid-May, were having a severe impact on fuel supplies, and a general curtailment of Luftwaffe operational activity was imposed (further weakening an already inadequate training regime). However, as the plight of the ground forces steadily deteriorated from bad to desperate, six new fighter units were committed to help save something from the wreckage. They made no difference. The pilots were as new as their aircraft; they were inexperienced and only superficially trained. Their ground support organization was disrupted by the need to pull back to avoid being overrun. Casualties were heavy, and nothing was accomplished.
Allied mastery of the air was the result of a long attritional struggle, not only in the west but over Germany and in the Mediterranean and eastern theatres as well. (And conversely, the Anglo-American assault on the Luftwaffe and German war production was of great benefit to the Red Army as it progressively smashed the main forces of the Wehrmacht.) This command of the air was a sine qua non, setting the conditions for eventual success on the ground. Without it, German reconnaissance aircraft would have detected the preinvasion buildup and probably would have penetrated the elaborate Fortitude deception that helped pin so many formations to the Pas de Calais. Without it, enemy airpower might have reacted effectively to the landings and against the shipping that supported them in the decisive early days. Without it, the interdiction campaign would not have been possible, and the enemy would have won the race to build up forces in Normandy, making a decisive counterattack possible. Had it not been maintained, the Germans would have been able to supply their forces properly and maneuver them in a timely and effective manner in reaction to Allied moves detected by air reconnaissance. Air supremacy also kept enemy air off the backs of the Allied armies, save for nuisance raids and ineffectual close air support. This was critical in many ways. Having failed to expand the bridgehead at anywhere near the desired rate, it became a target-rich environment crammed with fighting troops, headquarters, administrative areas, airfields, and the like. As it was, the Allies found that dumps and massed artillery, out in the open and uncamouflaged; nose-to-tail columns many kilometers in length; and other potentially lucrative targets could be offered without penalty. While denying effective and frequent air reconnaissance to the enemy, air mastery enabled the Allies to obtain timely intelligence at great depth. It also enabled artillery spotters to direct gunfire while denying this advantage to the enemy, an important combat multiplier. And it made possible the concentration of massive air-delivered firepower in close air support wherever it was desired on the battlefield.
Air Interdiction
Interdiction operations are mounted to destroy, neutralize, or delay enemy forces and supplies en route to the battlefield at such a distance from friendly troops that detailed integration of air and ground movements and fires is unnecessary. It was clear to the Overlord planners that such an air interdiction operation would be second in importance only to the achievement of air superiority; it would be a necessary prelude to and accompaniment for the invasion. Landings on an increasingly fortified hostile shore were going to be challenging, and even if they were successful, the enemy could build up his force levels faster by rail and road than the Allies could by sea across beaches without the benefit of a port.38 It would be necessary to disrupt and delay German reactions, compel the enemy to commit his forces piecemeal, and degrade their logistic support. To this end, both Air Marshal Sir Trafford Leigh-Mallory, C-in-C of the Allied Expeditionary Air Forces (AEAF—US Ninth Air Force and British 2 Tactical Air Force), and the Deputy Supreme Commander, ACM Sir Arthur Tedder, championed the Transportation Plan. This envisaged a sustained attack throughout Belgium and France to reduce the overall capacity of the railway system and all but prevent enemy rail movements. Such a massive undertaking could not be accomplished by the AEAF on its own; it would require the involvement, for a considerable period, of the heavy bombers and fighters of the United States Strategic Air Forces in Europe (USSTAF—Eighth Air Force based in the United Kingdom and Fifteenth Air Force in Italy) and the heavies of British Bomber Command.
Neither the C-in-C of British Bomber Command, ACM Sir Arthur Harris, nor the C-in-C of USSTAF, Lieutenant General Carl A. Spaatz, believed that the invasion of France was necessary to win the war. They thought bombing alone would bring Germany to its knees in a matter of weeks.39 For this reason, although they were enthusiastic about Operation Pointblank, they were reluctant to see any of their 5,000 heavy bombers and 2,000 long-range fighters diverted, as they saw it, to tasks in support of the invasion, as demanded by Leigh-Mallory and Tedder. In their view, attacks on the Luftwaffe in France, and especially the Transportation Plan, would simply provide breathing space for enemy fighter production to recover and detract from the campaign against what was now seen by Spaatz as the Germans’ key vulnerability: natural and synthetic oil production (in defense of which German fighters would have to accept battle and be written down). Eisenhower, who had a realistic understanding of both the limits of airpower and its indispensable strengths, was convinced that the invasion was necessary and that the proposed air interdiction operation was essential to its success. He had to fight a hard political battle to establish the principle that creating a firm Overlord bridgehead would take priority in the allocation of all theatre air resources until it was achieved.40 However, Spaatz’s arguments for the Oil Plan carried conviction. A significant reduction of German fuel production would impact both the army’s and the air force’s ability to fight; the great unknown was, given the indeterminate size of German reserves, how soon the plan would start to seriously curtail German operations. Spaatz was given the go-ahead for the Oil Plan’s implementation, provided it did not work to the detriment of the transportation attacks. Another less welcome diversion of effort was Operation Crossbow, wherein both strategic and tactical forces were increasingly sucked into attempts to suppress the enemy’s long-range (V) weapons targeted against England.
The Transportation Plan focused on railway marshaling yards and, especially, repair centres. The goal was to destroy locomotives and rolling stock en masse and thereby disrupt, reduce, and canalize rail activity and prevent its regeneration, creating a “railway desert.”41 These strategic air attacks would be complemented by the destruction of bridges by medium and fighter-bombers and the strafing of trains to further reduce capacity. German reinforcement and supply efforts would be forced to rely increasingly on inadequate road transport; however, road bridges would also be dropped, and armed reconnaissance would prey on vehicular columns. All German activity would progressively be slowed down and curtailed, fatally weakening the defense. Furthermore, attacks on ammunition and fuel dumps would deprive the enemy of prestocked reserves to live off while attempting to restore the logistic system.
By early June, the AEAF staff had concluded that fifty-one of the eighty rail centres on the target list for the Transportation Plan had been so completely destroyed that they required only the occasional dive-bombing to prevent repair. These systemic attacks were supplemented by armed reconnaissance sweeps throughout France and Belgium and even into Germany to locate and destroy trains. From late May, daylight movement was all but precluded. By 15 July, only 33 percent of locomotives in the French railway system were still usable, and it was impossible to employ the dwindling stock of undamaged locomotives effectively owing to the destruction of switching facilities and bridges. The second strand of the air interdiction operation was the dropping of bridges on two lines of interdiction, reattacking when required. The outer line ran east of Paris, from Étaples on the Channel coast, through Fismes, to Clamecy (about 120 km [75 miles] northeast and 240 km [150 miles] southeast of the capital, respectively), and the inner line ran along the Seine from Le Havre almost to Paris and along the Loire from Nantes to Orléans. The latter bridges were not hit until D-Day, for fear of compromising the Fortitude deception. There remained the problem of the Paris-Orléans gap, where the minor Eure and Loir Rivers were obviously less formidable barriers.42 Bridge bombing, especially on the inner line of interdiction, proved successful at an unexpectedly low cost. The Seine bridges were closed for 94 percent of the campaign (measured in “route days”), the Loire ones for 85 percent, but the “gap” bridges for only 56 percent.43 Rail traffic in France fell off dramatically as a result of air attacks. By 9 June, it was at 38 percent of the January–February level, and by mid-July, it was at 23 percent and practically at a standstill in northern France.44
The first, obvious impact of air interdiction was on the Germans’ ability to concentrate in an effort to repel and then contain the invaders. It appears that the casualties inflicted on German formations and units moving into Normandy were generally not significant (the memories of some German generals to the contrary notwithstanding).45 The delays were. The disruption of railway links with the region slowed their movement, usually severely; it forced some reinforcing groups onto the roads, where lengthy detours to avoid destroyed bridges, the inability to travel by day in flying weather, and fuel shortages combined to prevent their timely arrival or their arrival as formed units ready for combat. For example, 3 Parachute and 77 Infantry Divisions each took six days to complete marches of about 150 km (95 miles) from Brittany to the American sector of the front. II SS Panzer Corps, dispatched from around Lwow on 7–9 June for a decisive counterattack in the Caen area, did not arrive until the end of the month; it took as long to move the last 320 km (200 miles) as it had to cover the first 2,000 km (1,240 miles) from Poland. On average, marching troops could move only 24 km (15 miles) per day, and vehicle-borne ones around 50 km (30 miles).46 By the end of the first fortnight of the campaign, it was clear that the Allies would win the race to build up force levels. By 25 July, they had established a decisive superiority, thanks largely to air interdiction.
The second major effect of air interdiction was seen in the realm of logistics. The preinvasion buildup mandated by Hitler in his November 1943 directive had resulted in an influx of formations (of varying quality and freshness). This was not matched by an adequate logistic effort to sustain them. Ammunition was stockpiled for static, coastal defense, and port (fortress) divisions for three to four weeks of combat and for mobile divisions for two weeks (assuming rather optimistic rates of expenditure); fuel reserves were sufficient for two weeks. This relative deficiency did not trouble the high command, which believed it could rely on the railways. The air interdiction operations proved this belief fallacious. Moreover, Allied intelligence succeeded in locating many dumps, and air attacks destroyed them. For instance, the loss of the Domfront fuel depot on 13 June meant the loss of 40 percent of the fuel in Normandy; the Genvillers dump near Paris went up on 22 June with a POL (petrol, oil, and lubricants) reserve equivalent to the entire preinvasion stocks in Normandy, and more than one-fifth of the supplies shipped to the battle area were destroyed in transit. By the second week of the campaign, German Seventh Army was living hand to mouth, depending on daily deliveries from outside—a position officially acknowledged to be “catastrophic.” Army Group B estimated that it would run out of fuel by 20–25 July.47
The progressive disabling of the French railway system in critical areas forced the Germans onto the roads for resupply. There was insufficient mechanical transport available—perhaps half the required lift. Furthermore, to avoid the almost certain air attacks by marauding fighter-bombers, road movement was possible only in bad weather or during the six or so hours of darkness on June nights. Truck losses mounted, not only from air attacks but also from the increasing number of accidents and breakdowns (often irreparable, thanks to a shortage of spare parts). The need to use trucks to substitute for rail movement also increased fuel consumption. As the meager lift available to the army group’s quartermaster general eroded, combat formations had to send their own truck columns to the rear to collect supplies that should have been delivered forward, further limiting the mobility of front-line units and using more fuel.
By the opening of the Americans’ campaign-transforming Cobra offensive, the logistic situation of Fifth Panzer Army was far from comfortable but gradually improving. In fact, any failure to repulse the Anglo-Canadian attacks would not be attributable to inadequate resupply. There was no comparable improvement in the west, however; there, the situation continued to deteriorate. German Seventh Army’s stockpiles had been exhausted, a major reason for the eventual American capture of St. Lô. The army was more distant from its sources of supply, and fewer trains could be run across the Loire than through the Paris-Orléans gap; ferrying was also less well developed over the Loire than the Seine. And in the critical period immediately preceding Operation Cobra, air interdiction had once again cut the vital railway bridges at Tours and smashed the city’s marshaling yards; Seventh Army’s lifeline had been severed, and its restoration on 23 July was too late to replenish even minimal reserves of fuel and ammunition. Details of unit holdings have been largely lost—not surprising, given the chaos about to engulf Seventh Army—but several revealing statistics remain. When the American blow fell, 17 SS Panzer Grenadier Division was down to 1,000 rounds per machine gun and 30 per rifle; LXXXIV Corps had run out of critical 88mm armor-piercing ammunition by the end of the first day; 2 SS Panzer Division could not counterattack owing to empty fuel tanks in its panzers (which led to two Panther companies being abandoned by their crews and subsequently captured).48 The contribution of airpower to the success of Bradley’s army went far beyond the close air support emphasized by most soldiers.
Once a breakthrough was achieved and the Germans could no longer maintain a stable, positional defense but had a war of maneuver forced on them, the situation developed quickly. Given their low level of motorization, the Germans were ill equipped to cope with this increase in tempo. Allied air interdiction compounded their problems, whether by delaying reinforcement or, as they accepted defeat, hindering withdrawal. Either they confined their movement to the eight hours of darkness each August night or to days of bad weather—making them akin to a chess player able to make only one move to his opponent’s two—or they risked daylight movement, which almost always involved an air attack. Critical fuel shortages worsened as every unit had to displace and supply dumps and columns were hit. Air attacks destroyed few AFVs but significant numbers of soft-skinned vehicles (SSVs), and many more armored and unarmored vehicles were lost because their crews abandoned them in a panic or they ran out of fuel and were overrun by their pursuers.
Close Air Support
Close air support comprises air attacks on enemy targets that are in such close proximity to friendly ground forces that each air mission must be carefully integrated with the fire and movement of those forces. It stood a poor third in the list of air force priorities. Most senior RAF and US Army Air Force (USAAF) commanders regarded it with a degree of distaste as the most costly, the most difficult to control, and the least effective use of airpower. Moreover, most of the senior air commanders, particularly in the RAF, distrusted or were on poor terms with their land forces counterparts. For instance, Air Marshal Sir Arthur Coningham, commander of 2 Tactical Air Force, charged with supporting 21 Army Group, detested Montgomery; Coningham gave two of his three group commanders a hard time for being too close to the soldiers, and he managed to dismiss Air Vice Marshal (AVM) L. O. Brown on grounds of his “subservience” to the army.49 It was therefore fortunate that, at a critical operational level, relations were good: in First Army, General Bradley and later Lieutenant General Hodges worked well with Brigadier General Elwood R. Quesada of the supporting IX Tactical Air Command, and Lieutenant General Patton of Third Army got on famously with Brigadier General Otto P. Weyland of XIX Tactical Air Command; similarly, Lieutenant General Sir Miles Dempsey of Second Army and Lieutenant General Sir Harry Crerar worked well with the commanders of 83 and 84 Groups, AVMs Harry Broadhurst and L. O. Brown, respectively. Relations at lower working levels were generally excellent, as junior officers were less burdened by the baggage and prejudices of the past.
Despite its low position in the order of priorities, close air support became a normal feature of air operations in 1944. The decline of the Luftwaffe and the growing strength of the Allied air forces meant difficult choices were seldom necessary; there was usually enough airpower available to maintain air superiority or supremacy, carry out interdiction, and still allocate a generous amount of airpower to close air support. Thus, to take the example of a “typical” day, 18 July, IX Tactical Air Command and First Army allocated air effort for the next day as follows: 40 percent for close air support for First Army, 30 percent for close air support for Second Army, 20 percent for offensive fighter sweeps and combat air patrols, 10 percent for attacks on rail lines and other lines of communication.50 However, the mutual suspicions and even hostility of air and ground forces, dating back to the earliest days of airpower, led to divergent ideas on doctrine and prevented or delayed the creation and adoption of the joint concepts and organizational and equipment developments needed to ensure effective air-ground battle. Neither soldiers nor airmen really understood the problems and requirements, capabilities and limitations, of the other, Mediterranean experience notwithstanding. Coordination measures were generally inadequate and often misunderstood or abused. It took a long time to adopt a responsive, flexible system for the timely provision and direction of close air support. Thus, it was only in late July that IX Tactical Air Command and First Army adopted the concept of intimate cooperation between fighter-bomber and armored units in a joint team—armored column cover—and the means to implement it. Even then, despite its proven success, it was decried by traditionalists as doctrinally unsound and wasteful of resources.51 The British took even longer to adopt a similar system, the “cab rank.”
The main provider of close air support was the fighter-bomber, and in the P-47 Thunderbolt and the Typhoon in particular, the Americans and British had excellent delivery systems. However, in the semistatic or, at best, slow-changing conditions that prevailed in Normandy until Cobra, the weapon was of limited effectiveness. The Germans had become expert at concealing and camouflaging defenses dispersed and in depth to minimize the effect of both artillery and air attack. The ground, particularly the bocage, helped them. Lucrative targets were rarely on offer, and it was difficult to identify and then strike point targets with inherently inaccurate bombs and rockets. As the campaign wore on, with little in the way of gains, both ground and air commanders became concerned that close air support was not the important force multiplier they had expected it to be. On 6 July Brigadier General Weyland estimated that 80 percent of missions were falling short of expectations.52
It was another matter when the enemy could be detected concentrating for a counterattack. Massing made units vulnerable. Even then, however, the physical destruction fell far short of air force claims. For instance, during the Mortain battle of 7–10 August, in circumstances very favorable to the air attacker, IX Tactical Air Command and 2 Tactical Air Force together claimed 196 AFVs and 168 other vehicles destroyed and an additional 56 AFVs and 60 other vehicles damaged. In fact, detailed postbattle analysis on the ground showed that air attack accounted for only 21 AFVs and 12 other vehicles destroyed (although a few of the 15 armored and 26 other vehicles lost to unknown causes could probably be attributed to the fighter-bombers, and many of the 13 AFVs and 18 others abandoned intact or destroyed by their crews were probably given up owing to fear induced by the air attack). In other words, the pilots claimed they had destroyed roughly four times as much as they actually did (as well as more tanks and SP vehicles than the 177 actually possessed by the attacking XLVII Panzer Corps).53 This is not to suggest that airpower had only a minor effect on the battle. The prolonged presence of fighter-bombers over the battlefield exercised a profound adverse effect on German morale and was a major contributor to the halting of the attack and the enemy’s decision to take cover rather than advance. The same can be said of several other abortive German counterattacks.
There were other days when the Germans were compelled to offer dense targets for air attack. During the retreat that started in mid-August, the only alternative to being encircled in the Falaise pocket was the daylight movement of columns through the narrow gap that remained between its jaws and then back to the Seine. Unfortunately for them, there were several successive days of good flying weather, and the tactical air forces took full advantage. More than 7,500 AFVs and SSVs were lost. However, only a proportion of these were disabled by air-delivered weapons. For instance, of the 885 vehicles examined in detail in the pocket, only 359 had been damaged by air attack, and 526 had been abandoned or destroyed by their crews. Of course, many of those in the latter category had been given up because of congestion or panic caused by the fighter-bomber attacks, but a significant proportion, probably the majority, were out of fuel. Even in the most favorable circumstances for ground attack, air interdiction seems to have accounted, albeit indirectly, for more enemy losses than did direct strikes.54
Where the fighter-bomber really came into its own was during highly mobile operations, particularly the pursuit. Armored column cover and the British cab ranks meant that spearheads had an effective substitute for artillery, especially medium calibers, which were heavier and had a difficult time keeping up with high rates of advance. Once the systems were established, the speed, flexibility, and responsiveness demonstrated by tactical airpower proved to be a trump card. No longer did ground units have to wait at least an hour for requested air support to appear overhead. Hasty defensive and delaying positions could be hit from the air as soon as they were located and then attacked on the ground immediately afterward. Alternatively, the fighter-bomber flights could range ahead of their supported columns, seeking opportunity targets and providing useful intelligence at the same time. The seemingly ubiquitous presence of Allied aircraft was as demoralizing to the Germans as it was cheering to the British and American troops. To deal with larger or more difficult, more important targets, forces could be quickly diverted from other missions and firepower concentrated. Such a rapid response saved time and therefore increased the tempo of operations, keeping the enemy off balance and saving lives. Moreover, Quesada’s persistent efforts to develop a radar system for vectoring fighter-bombers onto ground targets paid off in August. During that month, IX Tactical Air Command aircraft were grounded for only three days, compared with eleven in July, even though the weather was no better.55
There was another, far more controversial form of close air support—the use of heavy and medium bombers to blast a passage through enemy defenses with carpet bombing to facilitate a breakthrough or take a fortress. Generals were in awe of the amount of high explosives that could be delivered from the air in a short time, with corresponding shock effect. A single Lancaster heavy, for instance, could deliver 6,350 kg (14,000 pounds) of bombs, the equivalent of a regiment of 5.5 inch guns firing for almost five minutes. Such aircraft seemed (rather superficially) to be the mid-twentieth-century equivalent of the siege artillery used to breach the fortifications of old. Despite the unpromising precedent of its counterproductive use at Cassino in March, this tactical employment of Bomber Command, Eighth Air Force, and tactical air forces’ medium assets was tried in six major operations in Normandy: Charnwood on 7 July, Goodwood on 18 July, Cobra on 24 and 25 July, Bluecoat on 30 July, Totalize on 7 August, and Tractable on 14 August. Ground commanders persistently claimed that their attacks had been significantly aided by the bombing. The fact that each operation, except for Cobra, ran into difficulties and fell far short of expectations was attributed to factors unrelated to the aerial bombardment; of course, if the commanders wanted to ensure future air support, they had to argue that. In reality, the physical results in terms of men killed and equipment destroyed were generally disappointing and not significant. When German defenders were dispersed in depth and well dug in, even accurate bombing lacked the density to cause significant losses. The disruption of command and control caused by cutting telephone lines and damaging radios was far more serious. Most damaging of all was the demoralization of those unfortunate to be caught within the bomb carpet. Provided the ground attack exploited these effects as soon as the bombing ended, before the enemy could restore cohesion, it had a good chance of making initial progress.56 This was often problematic, however, as the safety distance required to avoid casualties to forward Allied units was almost 3 km (2 miles); the attackers needed time to cover this safety zone and then negotiate their way over the moonscape created by bombing. Even carefully negotiated bomb lines did not eliminate short bombing, which, due to a variety of errors during Cobra, Totalize, and Tractable, killed a total of 299 Allied soldiers and wounded another 1,125.
Operation Cobra did achieve a breakthrough, which was subsequently attributed in large part to the saturation bombing of a box measuring about 3 by 7 km (2 by 4 miles) by 1,490 heavy and 380 medium bombers. The target area was defended by the Panzer Lehr Division, and the views expressed by its commander, Lieutenant General Bayerlein, in 1949 have been cited extensively in support of this contention. His memory, however, was fallible on some points, and his replies to questions were probably influenced by the desire, not uncommon among German generals, to attribute their defeat to airpower as a factor beyond their control. He exaggerated his AFV losses and probably personnel losses as well, although he was undoubtedly right to stress the air bombardment’s effect on morale. And it must be remembered that the initial German resistance was so effective that nowhere did the attacking Americans achieve their first-day objectives.57 The breakthrough probably owed less to the Eighth and Ninth Air Forces’ bombers than to the fact that Panzer Lehr—indeed, the whole German Seventh Army—was understrength, lacking both defensive depth and reserves, and critically short of ammunition. The powerful, concentrated attack by VII Corps on a narrow front and backed by more than 500 guns probably would have achieved a penetration without the bombing (which caused about as many American casualties [757] as German).58 The conversion of the penetration into a breakthrough and the subsequent maintenance of momentum that kept the Germans off balance owed much to IX Tactical Air Command. The system of armored column cover created by its commander, Quesada, played a key role in ensuring a high tempo of operations. Indeed, it would not be surprising if the generals mentally blurred the difference between the massive but possibly inconclusive bombardments of 24 and 25 July and the highly successful application of armored column cover from 26 July onward.
Air preparation was now regarded as an essential prelude to penetration of the enemy defenses when serious opposition was encountered. It would continue to be employed in clearing the Channel ports and the Scheldt estuary, breaching the West Wall (Siegfried Line), and forcing the Rhine. In his memoir, Eisenhower wrote that, by the time of Operation Cobra, “the emergency intervention of the entire bomber force in the land battle had come to be accepted as a matter of course.”59 Acceptance by senior airmen (except for Leigh-Mallory), however, was usually obtained with extreme reluctance and under protest. When the ground forces failed to achieve the promised breakthrough (everywhere except for Cobra), the air chiefs complained forcefully. The tactical failure of Operation Goodwood, despite 1,855 bombers (more than 80 percent of them heavies) dropping 7,700 tons of bombs, led ACM Tedder to write to Lord Trenchard on 25 July and admit they had been “had for suckers.”60 He urged Eisenhower to dismiss Montgomery as ground forces commander, a weakening of the latter’s authority that would have repercussions as the campaign wore on. Already resentful at the diversion of their resources from strategic targets under the Transportation Plan, the airmen regarded the employment of their aircraft as artillery on the battlefield as a misuse. As Tedder wrote to the Chief of the Air Staff on 25 October: “the British Army have for months now been allowed to feel that they can, at any time, call on heavy bomber effort and it will be laid on practically without question. . . . I am doing my best to get things straight, but I am sure you will realize that, the Army having been drugged with bombs, it is going to be a difficult process to cure the drug addicts.”61
In truth, air preparation by bombers was of doubtful value. The airmen were probably right to regard it as wasteful, as a panacea sought by soldiers ignorant of the limitations of the instrument but anxious to find some deus ex machina to break the stalemate and save them from additional losses. The number of occasions on which strategic airpower was diverted to tactical missions was relatively small, so the opportunity costs were not really significant. However, Tedder and the “bomber barons” were right to fear and resist the trend to involve it more and more, especially as the approach of autumn, and then winter, promised fewer flying days in which pressure could be maintained against the Luftwaffe and the critical oil industry targets. They were also correct to argue that the Oil Plan and disruption of the transport infrastructure within Germany were exercising a more powerful influence on the Wehrmacht’s ability to continue the war than any amount of bombing of the front line ever could. The relentless attack on synthetic oil production, combined with the loss of the Ploesti oil fields (the source of 25 percent of German oil supplies), overrun by the Soviets in August, reduced the production of aviation fuel from 175,000 tons in April to a trickle of 7,000 tons in September. This forced the Germans to withdraw their fighters from the battle fronts in a vain and costly effort to protect this vital resource.62 Dwindling supplies of fuel also severely hampered ground maneuver at a time when it was more important than ever.
Reliance on massive aerial preparations was often counterproductive for the ground forces as well. It could exercise a pernicious effect on planning. Air participation was very weather sensitive, both over the bombers’ bases and over the target areas. If a plan was dependent on thousands of tons of bombs, low clouds at the wrong time could wreck it (and an average of one day in three saw poor flying weather in France, let alone in the United Kingdom). The timing of bomber intervention in the ground battle had to be set in stone from an early stage. Bearing in mind the elder Moltke’s dictum that no plan survives contact with the enemy, this imposed a rigidity on the ground battle that boded ill for a successful outcome. This was particularly true of those phased operations in which a second bombing was planned for attacks on enemy positions in depth. This problem posed difficulties during Operation Bluecoat and ruined the promising Totalize offensive.
Airpower: Conclusions
Winning air superiority was a sine qua non for the invasion to succeed. Probably the least influential factor in the successful campaign to do so (directly, at least) was the bombing of factories responsible for fighter production. In 1943 the Germans turned out 10,059 fighters of all types, and 24,981 rolled off the production lines in 1944. The Luftwaffe’s major problem became not the availability of aircraft but the availability of adequate aircrews. Experienced, and therefore effective, pilots were lost much faster than they could be replaced, and the novices were poorly trained as instructors were pressed back into front-line service and the already truncated training programs, intended to produce more pilots faster, were further curtailed by fuel shortages. The offensive counter–air effort against air bases throughout the enemy’s depth, the later attacks on the oil industry, and the Germans’ forced acceptance of aerial combat even in adverse circumstances proved to be campaign winners.
Air interdiction likewise had a profound effect on the land campaign. The Allies had won the competition to build up combat power in Normandy by mid-July. Of course, this was not attributable solely to air action. The Fortitude deception inhibited the Germans’ ability to reinforce Normandy in time to make a difference. More important, though, was the fact that the Red Army had fixed the preponderance of German land combat power. At the end of May there were 54 divisions in France and the Low Countries (almost half of them static), 27 in Italy, 25 in the Balkans, and 22 in Scandinavia (including 7 in Finland, facing the Soviets), but 157 in the USSR.63 When the Germans sent reinforcements to Normandy in June and July, few could be spared from the eastern front (in fact, only II SS Panzer Corps was sent). But even if they had attempted to deploy more forces and sooner, air interdiction would have imposed severe limits on what they could achieve.
OPERATIONS BEHIND GERMAN LINES
Airpower was the principal means of carrying the struggle into the German rear areas, but it was not the only one. Underground resistance movements grew up in the occupied countries, and the Allies encouraged them. The Special Operations Executive (SOE) was set up in July 1940 on Churchill’s orders to “set Europe ablaze.” Its remit was twofold: to spread propaganda in occupied countries and to equip and train resisters. It was joined in its activities by the US Office of Strategic Services (OSS), established in June 1942 (although this forerunner of the CIA had additional responsibilities, including espionage). With the invasion of France in the summer of 1944, the British and Americans endeavored to support and direct the efforts of the resistance to aid the AEF, principally by interfering with German lines of communication. In acknowledgment of the important role the French resistance was expected to play, SHAEF, shortly after the landings, recognized the Forces Françaises de l’Intérieur (FFI) as a regular armed force of de Gaulle’s legitimate government of France.
Resistance Movements and Their Allied Helpers
Much myth, born of the desire to bolster national self-respect, has grown up about resistance movements in the Western countries conquered by the Germans. In truth, although only small numbers enthusiastically welcomed the conquerors, not insignificant sections of society were happy about the triumph of extreme right-wing ideology and the political and economic opportunities presented by occupation. By far the largest segment rejected active collaboration but would not go so far as to engage in active, or even passive, resistance. Most people preferred to get on with their lives and ignore the authorities, to the extent they could do so without inviting adverse consequences. Only a very small minority chose to join the underground, at least before the German defeat appeared imminent. Fear of betrayal and savage German responses to perceived terrorist acts, especially indiscriminate reprisals, certainly helped limit the number of resisters and make them unpopular.64 However, passive resistance became increasingly widespread as time wore on. This most commonly took the form of subtle, minor sabotage—mislaying files, frustrating telephone calls, misdirecting trains by relabeling freight trucks, and so on. As more time passed and people were emboldened by German reverses, this sometimes escalated into overt noncooperation, slowdowns, demonstrations, and strikes.
For the first three years or so of the occupation, resistance movements were small, inchoate, fragmented, and localized; many were communist inspired, although diverse political and social (indeed, criminal) elements were eventually drawn in.65 This limited flowering did not take place until later in 1943, when the German introduction of forced labor compelled young men to choose between unpalatable compliance and disappearing from official view; the growing intensity of the labor drives fed the underground with recruits from the réfractaires, although the vast majority were more concerned with remaining hidden than with fighting. However, as the Germans’ fortunes declined and the prospect of Allied victory grew, participation in the underground also grew, as did passive resistance. The ranks of the “September resisters”—those who joined as the Germans retreated—dwarfed those who had shown commitment while the outcome was still in doubt. For many, fighting the occupiers took second place to settling scores with collaborators and political or personal foes and establishing a favorable postwar political position. It was with this aim in mind, for instance, that the communist resistance precipitated the uprising in Paris on 19 August. Fearing both German reactions and communist success, de Gaulle and his military commanders urged an immediate American move on the capital.66
In the Soviet Union and the Balkans, the combination of mountains, forests, swamps, vast expanses, and low population densities made it possible for units of partisans, often of substantial strength, to undertake operations. An increasing flow of recruits and general cooperation from the population were guaranteed by the brutal ideological and racial policies adopted by the Germans in the east but not mirrored in the west (save, of course, for the “final solution” of the “Jewish question”). The geography of France and the Low Countries, and the much more selective use of terror by the occupiers, militated against the flourishing of the sort of partisan warfare that characterized the war in the east and southeast. In northwestern Europe only the terrain of the Vosges and the Ardennes was suited to guerrilla activity, and both regions were limited in terms of area and importance. The rugged and thinly populated Massif Central and the alpine plateau of Vercors near Grenoble were more suitable, and Maquis activity was greater there; however, both were far from any important German lines of communication. The only attempt to rise up against the occupiers was made in Vercors in mid-June, but it was savagely crushed in July. In regions of more immediate interest to the invaders, Normandy’s underground was very weak; by and large, the Germans and the Normans got along pretty well before the landings. For both historical and terrain reasons, there was a much stronger resistance movement in Brittany, which would become very active and be of much help to Third Army.
SOE and OSS propaganda had some influence in the occupied countries, and this increased as the war wore on and Germany’s fortunes declined. Their active branches provided arms for nearly half a million Frenchmen (and for fewer Belgians and Dutchmen), as well as training and communications. To support the invasion directly, ninety-nine three-man Jedburgh teams, trained in guerrilla warfare, were inserted between June and September to step up efforts. They were tasked with liaising with (and, if necessary, leading) resistance groups and organizing equipment drops so they could conduct actions designed to aid the field armies. Each army group and army headquarters had a Special Forces (SF) detachment to coordinate Jedburgh operations. They did not, however, have direct communications and had to work through SFHQ at SHAEF.67
To intensify pressure on the enemy rear, a British Special Air Service (SAS) brigade was deployed in support of the invasion. It consisted of two British and two French battalions and a Belgian squadron. Its tasks were to arm and train resistance groups, locate targets for the Allied air forces, and delay and disrupt enemy reinforcements and logistic activities. To these ends, the brigade conducted forty-three operations. The SAS came under the command of 1 Airborne Corps, not SFHQ.
Results of Special Forces and Resistance Activities
The SAS claims that it reported 400 targets for air attack; inflicted more than 12,500 casualties; destroyed or captured 640 vehicles; achieved 164 cuts of railway track and 33 derailments; and destroyed 7 trains, 29 locomotives, and 89 rail trucks. The casualty claims are probably exaggerated, and the other achievements added little to the destruction wreaked by the air forces. Nevertheless, the brigade fulfilled its mission. It is impossible to quantify the damage and casualties inflicted by the Jedburgh teams; their achievements are not amenable to objective analysis. However, it is clear that many of them had an impact, some of it considerable. More could have been achieved if the Jedburghs’ insertion had been more timely; the rapid advance that followed the breakthrough meant that several teams had hardly landed before spearheads arrived in their operating area.68 Both types of SF provided a level of professionalism that made the resistance groups they worked with much more effective. Their operations helped boost the morale of the occupied population, at least when they did not result in savage reprisals, and lowered that of the enemy; they also helped tie down German troops (albeit not of front-line caliber) and equipment.
The accomplishments of the resistance in aiding the Allied landings and advance are difficult to assess, as they are encrusted with legend and distorted and exaggerated by special pleadings, often politically motivated. The intelligence provided by the resistance was occasionally of great value (e.g., on the V weapons), but most of it was either too partial (in both senses of the word) or imprecise to be useful or of uncertain reliability. Sabotage of rail, power, and telephone lines was a useful supplement to aerial bombing, but only the latter could destroy high-value targets such as bridges or locomotive repair sheds. Ambushes and raids on German units were only harassing in nature, although they no doubt lowered enemy morale somewhat.69 Probably more important than sabotage in disrupting German communications was passive resistance—the subtle, often imperceptible sabotage by railway and communications workers described earlier.70
Behind German Lines: Conclusions
General Eisenhower has been quoted as saying that active resistance efforts were worth half a dozen divisions to him.71 This was probably an exaggeration designed to please the prickly de Gaulle. Despite the high level of publicity accorded to these activities during and after the war, they accomplished relatively little of direct operational significance. There were exceptions, however, in the wake of the German retreat—for instance, bridge seizures like that at Morlaix and Verdun in August and, notably, the securing, intact, of the Antwerp docks by the Belgian resistance before the arrival of 11 Armored Division. Tactically, resisters were frequently of value to the Allies in providing local knowledge that helped speed the advance.
The FFI, embodied as paramilitary units, proved most useful as an adjunct to Allied armies as the enemy withdrew. In Brittany 20,000 former resisters helped Third Army mop up the Germans left in the peninsula and mask the “fortress” ports into which most of them withdrew—indispensable help, given the early shift of Patton’s main effort to the east. During the army’s subsequent, rapid drive to the Meuse, a combination of XIX Tactical Air Command and FFI forces covered its long, exposed Loire flank. The most important contribution of the FFI occurred in the south, where the more favorable terrain, combined with massive withdrawals from Army Group G to feed the Normandy battle, offered great scope to the estimated 75,000 resisters and the reinforcing Jedburgh, SAS, and OSS operational groups. On 7 August Colonel General Blaskowitz had to report that he was no longer coping with merely a terrorist movement but with an organized military force in his rear; a week later, when the invasion started, he controlled only the Rhône valley and a coastal strip. The FFI helped prevent his demolition of the Mediterranean ports, and it harassed and speeded the German withdrawal. The decision was then made to integrate FFI units into First French Army to replace North African troops before the onset of winter, and by the end of October, more than 60,000 had been absorbed.
Even if later claims of their contribution were overblown, the Allies received a good return on their investment in SF. It could have been greater, however. Higher-level commanders did not really appreciate the potential of this new capability; in addition, insertion generally took place too late, and there were frequent communications and resupply problems. As a result, the operational-level impact of the Jedburgh teams was less than it could have been. Moreover, a faulty command and control structure prevented the synergistic coordination of SAS and Jedburgh actions. The fact that formations greatly appreciated the teams’ tactical assistance upon linkup (e.g., acting as guides, providing local knowledge and liaison with FFI contingents) was of only some consolation to the originators of the concept.72
OPERATIONAL-LEVEL INTELLIGENCE
In most armies before World War II (with the exception of the Red Army), senior generals had some degree of prejudice against intelligence. It was still associated, by implication, with the dirty business of spying—not an activity for gentlemen. Nor was it a likely path to promotion for talented and ambitious officers—indeed, it was a notorious dead end for military careers. Of course, there were some natural intelligence officers and some mavericks attracted by the seedy glamour and mystery who turned out to be good at it, but on the whole, intelligence was the destination of the mediocre. This was true of the prewar regular armies, but massive wartime expansion, especially in the democracies, brought in a whole lot of amateurs, many of them academics, who had fewer inhibitions about the job and proved very capable. But they usually had a difficult time establishing the idea that they were worth heeding. Most commanders did not expect much of their intelligence staffs, and their intelligencers reacted accordingly, hesitating to push unwanted appreciations onto strong-willed, irascible, and opinionated commanders; it was much safer to tell the old man what he wanted to hear, as Brigadier Charteris had done with his C-in-C, Field Marshal Haig, in the First World War.
This situation continued throughout the war in the Wehrmacht, where operational-level intelligence was generally poor to disastrous—especially on the all-important eastern front. To a significant extent, this was due to cultural factors. Germans—especially Nazis, whose thinking was skewed by ideological prejudices—looked down on Russians as untermenschen, racially inferior and therefore incapable of outsmarting the master race. As a result, the Wehrmacht continually fell for Soviet deception and was wrong-footed by most major Red Army offensives. (On average, during the third period of the war [1944–1945], the Germans missed over 50 percent of the Soviet buildup for each offensive and thus underestimated the attacker’s strength by a critical 25 percent.)73 That said, the Germans usually did little better against the Western Allies.
For the British and Americans, in contrast, operational-level intelligence blossomed as the war went on. This was due to a rarely interrupted run of successes that earned intelligencers the right to be listened to. It must be said, however, that intelligence became much weaker and patchier below army level. Tactical signals intelligence (SIGINT) was efficient, especially in gathering order of battle (ORBAT) material, but it was hampered by the German preference at division and corps levels for teletype or radio telegraph rather than voice radio communications (these low-power systems were more difficult to direction-find and intercept, and messages were usually encoded). Of fundamental importance, at the tactical level, intelligence was woefully slow to grasp some of the enemy’s concepts for defense (especially its depth and the distribution of resources within it). There was a comforting stereotype of the enemy as somewhat rigid, inflexible, and lacking initiative, a misperception that was almost 180 degrees removed from the truth. The result was a persistent underestimate of the Germans at the tactical level. This frequently led to attacks falling well short of expectations. Of course, the tactical failure of a corps or even a division, due at least in part to a faulty understanding of the enemy, could contribute to the failure of a theoretically sound army plan.
Allied Sources of Intelligence and Its Exploitation
The key to these operational successes was Ultra—the exploitation of the penetrated secrets of the German Enigma cipher machine used for topsecret radio traffic. Ultra decrypts, along with those from Magic (Japanese messages from Berlin to Tokyo), established a reputation for accuracy that could not be gainsaid. Ultra was probably of more intelligence value than all other sources combined. Once they overcame their inbuilt prejudice against intelligence in general and doubts about Ultra in particular, most generals came to rely on it (although Bradley did so somewhat late and with qualifications, as it seemed too good to be true).
Often sensationally, Ultra revealed enemy dispositions, formation strengths (personnel and equipment), supply states, and casualties. Even more important, it often revealed, at least by inference, enemy intentions and actual plans (with alternatives, should things go wrong). Never before in war had one side been given such insights into the enemy’s hopes and anxieties, strengths and vulnerabilities, resources and constraints, even his commanders’ habits of thought and their relationships with one another. The battlefield, Clausewitz pointed out, is “the province of uncertainty and chaos,” with “a great part of information being obtained being contradictory, a still greater part false and by far the greatest part of doubtful character.” Ultra removed much of that uncertainty for top Allied commanders, giving them an inestimable advantage over their German counterparts.74
This inexhaustible supply of priceless information, to switch analogies, put the Allies in the position of a poker player keeping his own cards concealed while being able to see those of his opponents. Had the Germans ever suspected that the enemy was reading their top-secret traffic, the supply would have dried up instantly (or after some spectacular piece of disinformation). For this reason, the distribution of Ultra-derived intelligence was restricted to army-level commanders and above. No reactions were permitted if the only source of information could have been Ultra. And great pains were taken to conceal the source of any information passed down to lower levels. (This suited commanders like Montgomery and Bradley, enabling them to claim to both subordinates and posterity insight and boldness where none actually existed.) Both for this reason and (though increasingly less often) because of time delays between German transmission, decryption, and dissemination to Allied HQs, Ultra was largely of operational value. However, there were times (more often, as the war wore on) when it was able to influence tactical actions too.
Still, Ultra had its drawbacks. German senior commanders had a natural preference for face-to-face meetings or telephone or teleprinter communications. When these means were used, Ultra was silent, but silence did not mean decisions were not being made and orders issued. Early on, there could be a massive time lag between a communication being intercepted and decrypted. But by the time the Normandy invasion was under way, decryption problems had mostly been overcome (especially for Luftwaffe traffic, which often revealed much about the ground forces). However, the process of decryption, translation, evaluation, and dissemination to army groups and armies always took time; for the information to be turned into intelligence and acted on required even more time. Events, especially in rapidly developing situations, could render the product passé—particularly at the tactical level. German intentions could change, or commanders might disobey orders, meaning that Ultra had apparently been misleading. And Ultra often gave only a partial picture—for example, an intercepted communication could be the answer to a question asked by telephone, or it could be the question, with the answer delivered by other means. It could not provide answers about states of training, morale, and combat effectiveness and other important intangibles, and if the wrong assessment was made, it could lead to costly failure (e.g., in operations to open up the Scheldt to make Antwerp usable and in the execution of Operation Market Garden).
In other words, Ultra told the truth, but not always the whole truth. Ultra was not the sole answer to all intelligence problems. Complementary sources were needed to produce a balanced picture or, in some cases, any picture at all. The principal source was air reconnaissance, both visual and photographic. With command of the skies, Allied aircraft could go pretty much wherever they desired, and their product was vital, both operationally and tactically; it included counterbombardment planning and mapmaking, pinpointing supply dumps and troop concentrations, and surveilling destroyed bridges. The army and air force Y Service provided radio direction finding and intercept—a very valuable source, but largely at the tactical level. The French and Low Countries’ resistance movements provided inevitably patchy information of widely varying quality; it was usually difficult to assess and often dubious. Otherwise, there was the usual variety of tactical assets, such as sound ranging to locate enemy artillery and mortars, patrolling, interrogation of prisoners, and so forth.
Allied Intelligence Successes in Normandy
Before the 6 June invasion, Ultra was of more limited value, as the enemy was able to rely on telephones or teleprinters, couriers, and personal meetings for a lot of communications that later required the use of radios.75 Nevertheless, it was important in providing some partial intelligence and in reinforcing other sources. After the landings, Ultra was the main source of operational intelligence and an often significant source of tactical intelligence.
Before 6 June the Allies built up a fairly comprehensive and accurate picture of German dispositions and strength in France and the Low Countries, especially (and especially important) of the mobile formations. Knowledge of which airfields were in use often defeated enemy camouflage measures; after the invasion, advance notice of movements and raids, including their timing, made specific, targeted counteractions possible. Revelations about casualties and manpower, equipment, and fuel shortages were very important in assessing general capabilities and in encouraging the AEAF to persist in the correct course of action. The success of Operation Fortitude in concealing the likely invasion sector was apparent. And most important to the conduct of the campaign, Ultra continued to confirm until late July that the Germans still expected the fictional FUSAG to launch a second, probably main assault, most likely between the Seine and the Scheldt. This, of course, was of inestimable help to the Allies. German armored formations that could have mounted damaging counterattacks in the buildup phase remained pinned for a time, as did, later on, infantry divisions that should have relieved them to provide mobile reserves. (The beauty of an unimpeachable source like Ultra is that you know the enemy has not seen through your bluff and is not stringing you along until he can pull off some terrible surprise.)
Field Marshal von Rundstedt and his successor as C-in-C West, von Kluge, misunderstood Montgomery’s operational idea. They both believed that the US sector was of secondary importance to the British sector in the east. They thought the main effort lay in the British offensive on the Caen-Falaise-Paris axis, which would be supplemented imminently by a FUSAG landing north of the Seine and also aimed at Paris.
Ultra and the Y Service kept tabs on Luftwaffe reinforcements, intended movements (including timing), basing, strengths, casualties, and supply states (not to mention intentions and battery locations for III Flak Corps), down to the small details; this enabled quite precise targeting of the offensive counter–air campaign and defensive actions. It thus helped ensure that the Allies enjoyed not just air superiority (which numbers would have assured) but air supremacy by early July. It also produced the exact locations of POL and ammunition dumps, enabling air attacks that quickly reduced the enemy to a hand-to-mouth logistic situation.
Throughout the period, intelligence generally had a good grasp of ground forces’ deployments, strengths, growing supply problems, and intentions. The continuing presence of the bulk of the German armor in the British sector showed that Montgomery’s scheme to pin the enemy’s main strength in the east to facilitate a breakthrough in the west was actually working. It was also clear that Army Group B was being ground down mercilessly: by 16 July, it had lost about 100,000 men and received replacements for only 12 percent of this wastage; by 6 August, losses had reached 141,000, although the replacement rate had doubled.
There was usually adequate warning of even tactical counterattacks. More dangerous operational-level blows were almost always anticipated and responses prepared. The earliest was disrupted and delayed by the bombing on 10 June of HQ Panzer Group West. The biggest, by the newly arriving II SS Panzer Corps, was defeated by the timely transition to the defense during Operation Epsom (from 28 June).
The intelligence picture on the eve of the breakthrough, starting 25 July, was both accurate and comprehensive. The locations of all but two divisions were known, and the deployment of German Seventh Army facing the Cobra attack was known in some detail, including the lack of even tactical reserves and ammunition and the commander’s belief that the defense would crack under serious pressure.
As Cobra developed, Ultra revealed three interesting things: the chaos into which Seventh Army quickly descended, its show-stopping shortages of ammunition and fuel, and the slowness of Army Group B to react effectively (insofar as it could, of course). It also suggested, if only by the lack of traffic, that the Germans would be surprised (as they were) by the British Bluecoat offensive designed to complement Cobra.
The (quickly fatal) error committed by the OKW was the launching of a counteroffensive from Mortain to the sea at Avranches. Although Ultra failed to give unambiguous warning of the attack until shortly before H-hour on 6 August, it did flag the prior concentration of four panzer divisions in the area just north of Mortain. The formations used in this failed attack remained in the area, and on 10 August it was revealed why: Hitler had ordered another, stronger attempt. The positioning of the bulk of German armor in an exposed salient at the farthest extremity of their line positively begged the Allies to embark on an encirclement operation. Both Ultra and other sources kept track of German reactions to the growing crisis and chaos as they tried to extricate themselves from disaster. The demise of the Luftwaffe in western France was also tracked.
Failures of German Operational Intelligence in Normandy
At the operational level, German intelligence failed in Normandy (as it did in most campaigns).76 This was partly a cultural problem based on the German assumption of superiority (“they can’t fool us”; ”they can’t decrypt our Enigma messages”); the mediocrity of most intelligence officers; commanders’ unwillingness to listen to those who threw cold water on favored projects or prophesied doom; and a degree of gullibility and ignorance in crucial areas that contributed to poor appreciations. And, of course, Hitler increasingly monopolized operational decision making, and he was not going to listen to naysayers who argued with his famous intuition. But the Germans’ intelligence failure was also a result of relying on poor sources and a lack of good ones.
The Germans had no equivalent of Ultra. They did have a generally efficient SIGINT setup, equivalent to the British Y Service. It provided 70 percent of their ORBAT intelligence and, owing to poor Allied communications security, frequent warnings of the timing and nature of attacks. Their patrolling, sound ranging, and other tactical means were also good. Although these were no substitute for operational-level sources, the Germans were frequently able to defeat, or at least contain, attacks at the tactical level and thus frustrate Allied operational plans.
Allied air supremacy denied all but the most fleeting and shallow penetrations of air reconnaissance. This changed on 2 August when the Germans’ new jet, Arado 234, flew the first of thirteen fast, high-level photoreconnaissance missions that month (apparently unnoticed by the Allies’ air defense). But this reconnaissance breakthrough was too late; the Germans had irretrievably lost the initiative and, indeed, any ability to substantially affect the outcome. Their photography produced only historical snapshots of the forces destroying the Army of the West.77
For higher-level intelligence, the Germans relied on agent reconnaissance. The Abwehr inserted scores of spies into Britain, but they were staggeringly ill trained and amateurish; MI5 rounded up all but one (he committed suicide). Those that could be were turned, and the others were imprisoned or executed. The double agents, manipulated by the XX Committee, were used to feed disinformation to the Germans. They, together with open sources, signals deception, and tolerated air reconnaissance of dummy concentrations, were the tools of Operation Fortitude—the deception plan for the invasion. This was so successful that it continued to influence German actions until late July. When Operation Cobra started on 25 July, the Germans believed there were still forty-two Allied divisions in FUSAG ready to land north of the Seine. (Like all successful deception plans, Fortitude played to enemy expectations rather than trying to create new ones.)
Army Group B intelligence reports tell the story of the German failure. Right from the outset, the Germans got things wrong. When the Allies started to land on 6 June, they achieved surprise as to both location and timing. Agent reports, confirmed by SIGINT and some air reconnaissance, had indicated that the main landing would be done by Patton’s FUSAG (concentrated in the southeast of England) between the Somme and Dunkirk. In addition, the Allies would need four consecutive days of good weather to land, and that situation did not pertain on 5 June (the Germans could not, as the Allies did, study weather patterns out in the Atlantic, so they were less well informed).
The fate of the invasion would depend on the relative rates at which the two sides built up their combat power. The Germans imposed a crippling handicap on themselves that ensured they would lose the race. OKW was slow to release the panzer divisions that might have been able to drive the invaders back into the sea. Hitler saw the Normandy landings as a secondary effort designed to draw forces away from the Pas de Calais, where FUSAG would make the main effort. The Germans continued to believe in the FUSAG threat until the last week in July, when a second landing disappeared from Army Group B’s intelligence appreciations. This persistence was partly due to the reluctance of intelligence officers and their commanders to admit mistakes and abandon preconceptions that formed the basis of a whole campaign plan; it was also due in part to grossly inflated estimates of Allied strength. Before the invasion, the Germans believed there were seventy-nine divisions in the United Kingdom; the actual number was thirty-seven, and most of the phantom forty-two were in the mythical FUSAG. Army Group B’s weekly report of 17–23 July maintained that the Allies had “at least 40 divisions” in Normandy (there were actually thirty-two, including two in the process of landing) and another fifty-two in Britain, of which forty-two were deployable.
Army Group B did no better when it came to assessing the intentions of 21 Army Group. Naturally, the Germans expected there to be a synergy between Montgomery’s army group and those of FUSAG. The main effort was believed to lie with Second Army (and later First Canadian Army), which would seek a breakthrough on the Caen-Paris axis. At the right moment, FUSAG would land in one of three places: between Calais and the mouth of the Somme, astride the Somme, or between the Somme and Le Havre. The last would form the other wing of a thrust on Paris, which was seen as a politically important objective in its own right. More importantly, its seizure would isolate Seventh Army in Normandy and open a short route over good terrain to Germany. Moreover, the start of the long-range weapons (V1 and later V2) offensive against London would compel FUSAG to make the Pas de Calais launching sites one of its objectives. Accordingly, the main effort of the defense, including its best formations and armor, was deployed on the eastern flank of the bridgehead to stop the British.
German intelligence failed to see the big picture, but it achieved some tactical successes. The most notable was predicting the axis and timing of Second Army’s Goodwood offensive on 18–20 July—although this was helped by protracted and ponderous preparations that were difficult to conceal. After this defensive triumph, there followed a string of more or less disastrous failures.
The next American offensive was expected, and it was fully appreciated that German Seventh Army, facing US First Army, was on the brink of collapse. What was not divined was the change in American methods. Instead of continuing to attack across the front, Bradley chose a Montgomery-style concentration on a restricted frontage with a large armored exploitation echelon. Operation Cobra, launched on 25 July, achieved the hitherto elusive breakthrough that marked the beginning of the end. Rather too late, two panzer divisions were committed to stop the rot, but ignorant of the size and shape of the problem, they were sucked piecemeal into an attritional grind.
On 30 July Second Army mounted its supporting offensive, Operation Bluecoat. This achieved surprise with regard to axis, being on the west end of 21 Army Group’s sector instead of the usual east side. II SS Panzer Corps was hastily pulled out of the line and redeployed to counterattack and restore the defensive front. It too attacked blind and failed to recover a favorable line, becoming bogged down in an attritional struggle.
Faced with an American breakout from Normandy into good tank country, Hitler decided on a counteroffensive from Mortain to the sea at Avranches to cut off those elements of Third Army that had broken out. Again, the 6 August effort had to be launched into the blue, as intelligence had only the haziest notion of which US formations were located where. The American forces (including air) were far too strong to be overcome by unfocused attacks, and the venture failed. In doing so, it left the cutting edge of Army Group B stuck in a salient and positively asking to be encircled.
An encirclement usually needs two wings, and First Canadian Army attacked on 8 August to provide the second. The Germans fully expected another imminent thrust down the Caen-Falaise axis, so surprise was not possible. In Operation Totalize, however, the Canadians achieved surprise through the use of novel tactics, undetected by German intelligence. Fortunately for the defenders, the initial success was not properly exploited, and the offensive largely failed.
By mid-August, Seventh and Fifth Panzer Armies were in headlong flight, having implemented the drill for escaping encirclement that had been worked out through repeated, painful experiences in Russia. Some idea of how, where, with what, and how fast the Allies intended to close the trap would have been very useful. However, intelligence provided little information of any value. It certainly failed to obtain any clue as to which of the three courses assessed by Army Group B would actually be adopted by the Allies.
Given the Allies’ intelligence dominance in Normandy—unparalleled in military history—the Germans did pretty well to keep going as long as they did. The fact that so many German soldiers escaped to fight another day (and fight hard, at that) was a tribute to the skill and determination of those soldiers and their leaders; it owed nothing to their intelligence support. But it did owe quite a lot to the failings of Allied generalship and to faults in British and American doctrine and training, which will be discussed in the next chapter.
CONCLUSIONS
Even before the opening of the Cobra offensive, the Allied armies firmly held the initiative, and they had attained a potentially decisive superiority in combat power to exploit it. Their air forces had total mastery of the skies and could deliver formidable firepower wherever and whenever they chose (subject only to the weather). Their supply state was healthy. They had a clear, often detailed intelligence picture. The Germans, by contrast, had many hollowed-out formations. Their defense was stretched very thinly, especially facing the Americans in the west; they lacked operational reserves, and even tactical ones were inadequate. The front-line troops never saw a German aircraft. The logistic situation was poor in the east of Normandy, and serious combat could be sustained for no more than a few days in the west. The Germans were blind as to enemy intentions and were forced to rely on precedent, prejudices, and guesswork to prepare for the next Allied onslaught.
Seventh Army was bound to crack, probably sooner rather than later. An American breakthrough would lead to operations that assumed a fast-changing, maneuver character. Once the stability of the defense was lost in one sector, maintaining a positional defense in the other would become steadily less tenable as its flank became more and more exposed. But the Wehrmacht was no longer capable of conducting maneuver warfare. A lack of mobility and fuel would inevitably lead to many German units being caught in encirclement or overrun by their more mobile opponents.
However, the Allies would face problems as well. They had built up impressive stocks in the bridgehead but, because of their own air interdiction, would lack railway transport. These stocks would have to be moved timeously and in adequate quantities to support a long pursuit followed by renewed heavy fighting. The logisticians fully appreciated the problem and repeatedly reminded commanders and their G3 staffs about this reality. The SHAEF plan for post-Normandy operations was predicated on the possession of Brest and other Breton ports, in full working order, and an operational pause of about thirty days while forces, supplies, and the means to move them were built up for the war-winning offensive. Absent these preconditions, the culminating point of the offensive would come quickly.78 General Eisenhower fully understood the concept of the culminating point (he had read Clausewitz’s On War not once but three times and had been examined on the content by his mentor, Major General Fox Connor).79 He also understood logistic constraints. His stated strategic aim (as a good Clausewitzian) was destruction of the German armed forces, which, in the west, were grouped mainly in Normandy. Logically, given the imminence of Allied culmination, these Germans would have to be destroyed in Normandy and its immediate environs, not merely pushed back with heavy but possibly restorable losses. If the war was to be concluded rapidly, it would require a single-minded concentration on the annihilation of Seventh and Fifth Panzer Armies before the Allies’ offensive impetus ran out of steam, as it inevitably would due to logistic overstretch and fatigue. It is unclear whether Eisenhower or his principal subordinates fully grasped this point. Certainly, in the event, the AEF failed to achieve this goal as a result of the dissipation of their efforts.