At full strength, Terauchi’s five field armies each had around fifty thousand men, mostly combat troops organized into two or three infantry divisions plus tanks and extra field artillery. Roughly, therefore, 250,000 Japanese troops would have been involved in the invasion. DeWitt had around 172,000 troops under his command, though many were staff personnel at the various posts, or assigned to the especially labor-intensive Coastal Artillery Corps positions.
As previously noted, the only Regular Army Divisions were the 3rd Infantry at Fort Lewis, Washington and the 7th Infantry at Fort Ord, California, and there were two National Guard divisions stationed on the West Coast. There were also about seventy-five thousand Navy, Marine Corps, and Coast Guard personnel within the Western Defense Command area, but the only combat troops among them were fewer than fifteen thousand men in the newly reactivated 2nd Marine Division in San Diego.
It is important to underscore how isolated the units in California were from those in the Pacific Northwest. As I was reminded on a recent drive over this route, at modern Interstate highway speeds, Fort Ord (now CSU Monterey) is separated from Fort Lewis (now Joint Base Lewis-McChord) by at least 14 hours. At military truck convoy speeds on the two-lane highways as they existed in 1941, especially in December when heavy snow was probable in the Siskiyous, the journey, if a shift of personnel was deemed necessary, would have taken several days. The Japanese would have known of this bottleneck and would have made it a high priority for sabotage.
Had a Japanese sabotage campaign launched immediately before the invasion been successful, it would have sown confusion among the defenders and the residents of the Pacific Coast. It also would have prompted demands from politicians at every level as well as the press that DeWitt disperse his forces to prevent further sabotage—at a moment when the concentration of forces would have been of paramount importance.
In 1942, in historical fact, the Japanese 16th Army defeated an Allied force of equal size in Java within a week. In Malaya and Singapore, the roughly thirty thousand men of the IJA 25th Army defeated a British Empire force of more than one hundred thousand. These facts effectively dispel the notion, coined by Voltaire in 1770, that “God is always on the side of the big battalions.”
For DeWitt, his powerful, well-manned Coast Artillery organization would have been a blessing and a curse. Has the Japanese attempted to move directly against any of the major Pacific Coast ports, for example, trying to force the Golden Gate, they would have faced formidable firepower. At the same time, however, the fixed coastal batteries tied down a sizable number of troops, and they could have been easily outflanked. If, as Lieutenant General Tomoyuki Yamashita would do, famously and successfully, at Singapore in February 1942, the invaders had avoided a direct attack on the harbor entrances guarded by coastal guns, they could have made successful landings. DeWitt probably would have brought more field artillery to the battlefield than Terauchi would have had, at least initially, but, by all estimates, the American stocks of ammunition would have been spent within a few days at best. The tanks available to the two sides were evenly matched. The M3 Stuart light tank and the Japanese Type 95 were similar in size and armament (both had a 37 mm gun as their main armament), but, according to Stilwell in his diary, maintenance issues had reduced the number of M3s available at Fort Ord to just six.
For the sake of this “What If . . .?”, let’s assume that D-Day would have been Sunday, December 14, and arbitrarily assign the field armies to specific locations. The 14th Army under Lieutenant General Masaharu Homma would land in Washington and/or Oregon; the 15th Army under Lieutenant Shojiro Iida would land at San Francisco; and the 16th Army under Lieutenant General Hitoshi Imamura would land at Monterey Bay. Meanwhile, commanded by Lieutenant General Takashi Sakai, the 23rd Army would land north of San Diego. The attack on Los Angeles would fall to Hideki Tojo’s old friend and professional rival General Yamashita and his 25th Army.
A surprise attack might have been achieved as it was at Pearl Harbor, but it is likely that at least some of the Japanese invasion forces would have been detected by American patrol planes a day or two ahead of the landings. However, their exact destinations would have been open to speculation, and there would have been little that the U.S. forces present at the time could have done to stop them.
Arrayed against the Japanese thrust into the Pacific Northwest would have been the forces of the Northwest Sector of the Western Defense Command, under Major General Kenyon Joyce whose headquarters were at Fort Lewis. Within this organization, Joyce two coastal artillery regiments at Fort Worden, which guarded the approaches to Puget Sound, and the 3rd Infantry Division under Major General John Porter Lucas and the 41st Infantry Division under Major General Horace Fuller, the latter a National Guard unit.
When he received word of an impending Japanese invasion deemed likely, Joyce might have deployed his two divisions to the area of Grays Harbor and Willapa Bay to stop the amphibious invasion, and he certainly would have kept at least part of the force back to protect the U.S. Route 99 approaches to Seattle and Tacoma. Knowing that he also had responsibility for protecting Portland, he might have sent troops south to that city.
General Homma would likely have concentrated his full force at Willapa Bay, but he may also have availed himself of the opportunity for an unexpected landing at Newport for one of his three divisions. When he learned of this, Joyce would have perhaps sent his 41st Infantry Division to Portland to defend the city, and possibly to drive south on Route 99 to meet the Japanese before they could reach Portland. In any case, Homma would have had the initiative, and Joyce’s deployments would have been based on no small amount of guesswork.
Even with some opposition, the Japanese, landing in the predawn hours of December 14, would have consolidated their beachhead at Willapa Bay by the middle of the day. By that time some of the troops on the tip of Homma’s spear could have been on their way to capturing Aberdeen, adding a second port at Grays Harbor at which to unload transport ships. By that time, the troops that landed at Newport would have been ready to begin their drive on Portland.
In Malaya, the Japanese famously used bicycles to transport their troops on the excellent paved roads built a few years earlier by the British. In the United States, where automobiles were more common than in the Far East, the Japanese might have preferred to use purloined motor vehicles. Indeed, as in Malaya, the Japanese might well have limited the number of motor vehicles in the invasion force, deliberately planning to rely heavily on stolen cars. The Japanese probably also would have brought bicycles to the Pacific Coast, and, given the availability of fuel, they might have included motorcycles for reconnaissance.
As a precursor to any landing, the aircraft from the Akagi and Kaga of the Rear Admiral Chuichi Nagumo’s 1st Carrier Division would have launched dawn attacks against the USAAF at Paine Field, McChord Field (adjacent to Fort Lewis), and Portland Airport. If things had played out as they actually did at Pearl Harbor and in the Philippines, many American aircraft would have been destroyed on the ground, and any aircraft that rose to meet the enemy probably would have endured heavy losses as well. Among the second wave targets would have been Fort Lewis itself and the Bremerton Navy Yard on Puget Sound, where the battleship USS Colorado was being refitted.
The distance from Aberdeen to Olympia was only about an hour at highway speeds on U.S. Route 410, with Tacoma and Fort Lewis less than an hour beyond on Route 99 northbound. The pace of any Japanese advance would have been much slower because, after securing a beachhead, the force would have paused to allow for the unloading of vehicles, such as tanks, and supplies. Furthermore, given that the top highway speed of the Type 95 tanks was around thirty mph, and that the tanks would have slowed down in order to allow supporting infantry and artillery to keep pace, the Japanese spearhead might have taken a couple of days to reach Olympia.
Assuming that he would keep most of Lucas’s 3rd Infantry Division in reserve, Joyce would probably have been forced into a race to Olympia with Homma’s spearhead. Any American forces advancing to meet the invaders, however, probably would have been slowed by streams of refugees escaping north toward Seattle, and probably clogging the southbound lanes that Lucas needed to move troops.
As soon as a landing force at Newport, Oregon, had been able to round up a sufficient number of vehicles, it could have made their way to Oregon’s state capital Salem, by way of Albany, in a few hours against little or no organized resistance. Perhaps, Homma would have ordered a motorized coup de main to seize the city.
In any event, as they would have for American forces, northbound refugees on Highway 99 and other roads probably would have slowed the advancing the Japanese between Salem and Portland. While they could not have stopped the Japanese advance because of their lack of heavy weapons, as well as effective command and control, home guards, state and local police, and self-generating group of guerrillas also might have hindered it, if only slightly. It is probable, therefore, that the invaders would not have reached Portland until December 16 or later.
Shifting south, it would still have been dark on the morning of December 14 when the first troops from Shojiro Iida’s 15th Army began to disembark into landing barges for their assault on Ocean Beach in San Francisco. Although General DeWitt probably would have ordered a blackout as soon as he had received warnings of an approaching invasion force, there is every reason that it would have been as spotty and ineffective as it actually was that week. In fact, had advance Japanese raiding parties been able to attack the electrical grid, their actions would have been more effective in imposing a blackout than any public efforts to do so. In any case, there probably would have been sufficient light to orient the barge operators and the troops could land with relative ease. These initial landings would have been largely unopposed, and any opposition from home guards and, police would have been brushed aside. Behind the advance elements of the invading force, heavy equipment, such as tanks and artillery, would be unloaded after daylight.
At his headquarters at the Presidio, General DeWitt would have faced a dire situation. Probably, Japanese aircraft would have targeted his headquarters and, if their strikes were successful, DeWitt’s ability to keep up with events and exercise effective command throughout the theater and the more immediate area of San Francisco would have been severely curtailed.
Furthermore, the military police and a few infantry troops assigned to the Presidio would have been too few in number to intervene effectively in the Battle of San Francisco. The best they could have done was to protect the Presidio itself.
The majority of the soldiers then in the San Francisco area would have been those who manned the forts protecting the Golden Gate. The good news, as DeWitt would have been informed, would have been that the enemy had not tried to pass through the Golden Gate. The bad news, of which DeWitt need not be reminded, would have been that his big coastal guns—especially the casemated sixteen-inch rifles—could not engage the invasion fleet located south around Point Lobos.
Once the first Japanese regiment or two were ashore, they would have begun to march or drive, depending on how many motor vehicles they could have seized, toward the heart of the city—and the Presidio. The only thing that would have slowed the Japanese advance, besides improvised roadblocks, would have been the thousands of San Franciscans attempting to flee the city.
The forces on the ground would have been supported by naval gunfire from battleships and cruisers and the aircraft of the Soryu of the 2nd Carrier Division, then commanded by Rear Admiral Tamon Yamaguchi. The Japanese naval aviators would have struck at first light throughout the Bay Area. Their initial targets would have been the Mare Island Naval Shipyard and Hamilton Field in Marin County, both north of San Francisco. The naval air station at Moffett Field, thirty-five miles south of San Francisco, which had been a major center of rigid airship operations in the 1930s, was now only lightly used as a USAAF training facility. Meanwhile, at Alameda Naval Air Station across the Bay from San Francisco, facilities for a major future presence were still under construction, and there were only a few patrol planes based there.
If some of the P-40s of the IV Interceptor Command were in the air that morning, they might have enjoyed some success against the attackers. Over time, however, Japanese attacks on American airfields would have denied the fighters the ability to operate in an effective manner. It might have taken more than a day or two, but it might have happened as quickly as it did at Clark and Nichols Fields in the Philippines, and the USAAF would have lost the air battle over San Francisco.
On the ground, the Japanese would have probably reached the city’s huge beaux-arts City Hall, the dome of which is taller than the U.S. Capitol’s, sometime on the first day. Iida’s forces also could have bypassed City Hall in order to capture a far more valuable prize, the Port of San Francisco. If those facilities had been captured intact—and there is little reason to think that such would not have been the case—any follow-on build-up of Japanese forces would have been fast and efficient.
What would have—could have—General DeWitt done on that first day? He might have tried to call his subordinate commanders—Joe Stilwell in San Bernardino, Major General Walter Wilson, the commander of the III Corps at the Presidio of Monterey, and Major General Charles White, who commanded the 7th Infantry Division at Fort Ord.
As soon as patrol planes detected and confirmed Japanese ships offshore a day or so earlier, DeWitt would have huddled with Fourth Air Force commander Major General Jacob Fickel and Brigadier General William Ord Ryan of the IV Interceptor Command, who both had their offices inside the Presidio. DeWitt would certainly have been in touch with Admiral John Wills Greenslade of the Twelfth Naval District, who maintained his office in San Francisco.
On that first day, DeWitt would have contacted local officials, such as Mayor Rossi and Chief Dullea. He would have tried to get in touch with the state governors, although both Olympia and Salem would have been in danger of imminent ground attack. If Japanese saboteurs had managed to cut telephone lines and Japanese air attacks had damaged his headquarters, his attempts to contact these men would have been fruitless. If he had been able to reach any of his ground commanders and officials, they probably would have told him that their hands were full and that they would have been unable to lend him any assistance in the defense of the immediate San Francisco area. At sea, Greenslade’s entire available force at Mare Island consisted of three destroyers, which might have put up a valiant defensive action against the invasion fleet, but one that was doomed from the outset.
Almost certainly, his commanders and public officials would be calling DeWitt, begging for assistance that he could not give. Almost certainly, reports of real and imagined (and exaggerated) Japanese actions would have flooded his headquarters, denying him the ability to get a hold of the actual situation. Columns of smoke rising from the city and in the direction of Hamilton Field and Mare Island would only have heightened his anxiety. Perhaps, the best he could have done was to hold the southern approaches to the Golden Gate Bridge long enough to allow some civilians to evacuate the city, and for he and his headquarters staff to escape into Marin County in hopes of organizing future resistance.
As DeWitt dealt with an increasingly chaotic situation in San Francisco, his subordinate commanders in the Monterey area would have been dealing with their own problems. As elsewhere in the theater, the day would have begun with Japanese air attacks in the early morning. Aircraft from the Hiryu, the other 2nd Division carrier, would have attacked Fort Ord, bombing and strafing barracks, tank and artillery parks, and headquarters facilities.
It is doubtful that Lieutenant General Hitoshi Imamura would have landed his 16th Army in Monterey Bay, as doing so would have thrown out his forces directly against the 7th Infantry Division. More probably, he would have mounted a diversion to draw Wilson and White southward. Perhaps the IJN could have bombarded the picturesque little town of Carmel, and the entrance to the Carmel Valley, four miles south of Monterey. If Wilson and White believed that this bombardment was the preliminary to landings in Monterey Bay, they would have moved troops into position to thwart it—and left the actual beachhead, forty miles to the north, between Santa Cruz and Watsonville, undefended.
The mobility that unchallenged sea power would have granted Imamura would have provided him many options for action. He might have sent two divisions ashore in order to meet Wilson and White and landed his third one hundred miles farther south on the coast near San Simeon with the purpose of engaging and defeating the 40th Infantry Division, commanded by Major General Ernest Dawley and based at Camp San Luis Obispo, as early as possible in the campaign.
Alternatively, Imamura could have kept his entire command intact to ensure the defeat of the 7th Infantry Division before turning his attention to the 40th Infantry Division. Assuming that he had prevailed in the Battle of Monterey Bay, Imamura would have moved his army, minus a force to garrison Monterey and nearby Salinas, south, down Route 101, through the broad and level, Salinas Valley, to San Luis Obispo, 150 highway miles away. Just north of the city, however, the highway reaches a roadblock of rugged mountains and crosses the very steep Cuesta Grade, a choke point and an ideal defensive position. Dawley almost certainly have established a defensive line there before a battle that probably would have taken place around December 21. Confronted by such a situation, Imamura might have sent his army into a head-long frontal assault against the Americans or, as occurred in the Southeast Asia campaign in 1941 and 1942, mounted an amphibious assault in regimental strength north of Morro Bay, roughly thirty miles to the rear of Dawley’s roadblock. Confronted by the possibility of being surrounded, Dawley might have ordered a retreat, and, considering that breaking contact with an enemy and conducting an orderly retreat is a challenging task even for regular army troops with combat experience, this retreat could have turned into a rout for the National Guardsmen.
In Southern California, there would be a vast air-land-sea campaign, with battles spanning nearly 200 miles of the California coastline.
As noted in the previous chapter, the opening gambit would have been the naval Battle of San Diego, for which Yamamoto would have set aside the world’s most advanced aircraft carriers, Shokaku and Zuikaku of the 5th Carrier Division commanded by Rear Admiral Chuichi Hara. This battle would be aimed at finishing—or at least continuing—the destruction of the U.S. Navy’s Pacific Fleet.
Alternatively, Hara might well have positioned one of his carriers farther north of the other so that its aircraft could have struck the USAAF’s main facility in the area, March Field in Riverside, California. Such a strike would have done much to prevent American airpower, such as it was, from influencing future operations.
Japanese strikes against the U.S. Navy in San Diego probably would have delayed the amphibious operations for a day in order to ensure that they could be supported by the aircraft from both Shokaku and Zuikaku without distraction. The 23rd Army under Lieutenant General Takashi Sakai would have begun with predawn landings on the coast near San Clemente, whereupon the Japanese would turn south toward San Diego, only fifty miles away. After having secured San Diego, Sakai could then have pivoted his army northward and headed toward Los Angeles and Long Beach, acting as the southern side of a pincer movement with the 25th Army that would have been driving from the north. That would have been the plan. However, in his assault on San Diego, Sakai’s army would have been met by the 2nd Marine Division, based at Camp Elliot and commanded by the imperturbable Major General Charles Price. Price may well have dispatched his Marines to meet the invaders as they moved south from San Clemente. If he had, there is no doubt that the Marines would have inflicted serious casualties on the Japanese and disrupted whatever timetable Sakai had set for the 23rd Army’s operations. Yet, given Japanese air supremacy and the limited stocks of ammunition and other supplies available to his division, Price could not have held the Japanese back for long. In the end, he probably would have ordered a fighting retreat toward the east, hoping to preserve as much of his unit as possible for a future counteroffensive.
The Battle of Los Angeles would have been an enormous undertaking in urban combat. While the cities of the Bay Area were densely populated and highly concentrated in 1941, the population centers of Southern California were already showing the evidence of suburban sprawl for which they would became famous after World War II. Within the 4,058 square miles of Los Angeles County alone, there were 2.8 million people, 40 percent of the California total. By December 1941, the largest city captured by the Japanese had been Shanghai with a population of 1.5 million. It took the Japanese Army two months to take Shanghai in a costly and destructive battle.
An unopposed landing on the broad strawberry fields of Oxnard would have had a strong appeal to Yamashita. However, it would have taken two days or more to reach downtown Los Angeles, so a direct assault against Los Angeles on Santa Monica Bay might have had the appeal of expedience. As in San Francisco, the bulk of U.S. soldiers in Los Angeles were assigned to Coast Artillery forts. Given this lack of substantial U.S. Army maneuver forces in the Los Angeles area, therefore, Yamashita could have taken the same direct approach used by Iida in San Francisco. Like Iida, Yamashita would have emphasized swift movement in the first few hours, knowing that, after the initial shock of the invasion had worn off, refugees would have clogged the local roads and highways. Therefore, a landing at Santa Monica Bay would have been considered the best option.
Of course, a landing within full view of the homes of movie stars in the Hollywood Hills would have been, dare we say it, cinematic. Likewise would have been the sight of Type 95 tanks on Hollywood Boulevard, though the actual invasion routes would have probably followed such parallel boulevards as Beverly, Pico and Santa Monica.
The city of Santa Monica, at the north end of the bay would have provided the threshold for a direct push toward downtown Los Angeles, as well as an opportunity to capture the Douglas Aircraft Company headquarters at Clover Field inside the city.
At the center of the bay, Los Angeles Airport was a literal stone’s throw from the beach and within sight of the factories of Douglas Aircraft in El Segundo, Northrop in Hawthorne, and North American Aviation in Inglewood. Capturing these intact would have been desirable and probably a high priority for the Japanese. It is hard to say if the Americans would have been able to seriously damage these factories before the Japanese reached them. Attempts might have been made to destroy the factories to keep them from being used by the enemy, but considering how quickly the Japanese would have reached them after coming ashore, it is doubtful that there would have been time for extensive sabotage.
Additional landings at the southern end of San Monica Bay, between Manhattan Beach and Redondo Beach, would put the Japanese at the doorstep of strategically important petroleum facilities, and provide troops of the 25th Army a southbound gateway, via the Pacific Coast Highway and Hawthorne Boulevard, toward the ports. Once those were in hand, a great stream of ships from Japan would flood in, carrying reinforcements and the civilian technicians and administrators who would run California’s most populous region as a virtual Japanese colony.