20
Strategic Disaster
The Tet Offensive commenced on January 31, 1968, the last day of the Lunar New Year and the most important holiday in the Vietnamese year in both the North and the South. The NVA planned it as a one-two punch consisting of a “General Offensive” and a “General Uprising,” resulting in the overthrow of the GVN. Its outcome was a double-edged irony for both sides.
Recent scholarship indicates that Le Duan and his “War Politburo” planned the Tet Offensive. After years of indecisive warfare, Le Duan wanted to find the American breaking point. While Ho Chi Minh and Giap were urging caution, “Le Duan and his hawks in the Politburo strove for total victory through an ambitious and risky large-scale offensive aimed at the cities and towns of South Vietnam.” Le Duan found a more compliant general to implement his risky military strategy in Senior General Van Tien Dung. Dung had shrewdly positioned himself to replace General Nguyen Chi Thanh, who had commanded NVA forces in the South during the Ia Drang battle and who later died from a heart attack on July 6, 1967, under murky circumstances. It was Le Duan and General Dung who unveiled their plans at a high-level meeting in Hanoi on July 18–19, 1967. They proposed that while NVA main-force units tied down American troops away from urban centers, the VC would mount large-scale attacks on the cities and towns throughout Vietnam to incite a mass insurrection that would topple the GVN regime in Saigon.1
The success of the plan depended on three assumptions: (1) the ARVN would collapse under the weight of the countrywide general offensive (map 20.1), (2) the people of South Vietnam would follow through with a general uprising, and (3) American political will to continue the war would crack in the face of the overwhelming assault. None of these things happened as predicted. Neither the NVA nor the revolutionary movement achieved the military objectives of the offensive or the political objective of the uprising. However, the American public did undergo a major shock. As NVA brigadier general Tran Do, who was one of the Tet planners, retrospectively remarked,
In all honesty, we didn’t achieve our main objective, which was to spur uprisings throughout the south. Still, we inflicted heavy casualties on the Americans and their puppets, and this was a big gain for us. As for making an impact on the United States, it had not been our intention—but it turned out to be a fortunate result.2
Map 20.1. The plan of First Secretary Le Duan and General Van Tien Dung to attack all major cities and towns in South Vietnam failed to deliver a military victory, but it undermined the American public’s confidence in the war.
Source: USMA Atlases.
For MACV, the outcome appeared to be a tactical victory. The NVA and the VC achieved significant military surprise, but they were unable to exploit it. The NVA planners had violated Clausewitz’s principle of mass. By attacking everywhere, they had superior strength nowhere. The general uprising failed to occur, even in Hue, where General Tran Do took personal command of NVA and VC forces.3 Across the country, as Tet unfolded, the offensive was launched without full coordination of enemy units, north and south, with respect to timing. Even with the advantage of surprise, the NVA offensive achieved few military gains.
The Viet Cong’s efforts in Saigon were piecemeal, uncoordinated operations. A nineteen-man VC platoon breached the wall of the US embassy compound in Saigon. It never penetrated into the chancery. This force was wiped out in a matter of a few hours. However, the psychological effect was devastating to the Johnson administration’s credibility. Images of the American symbol of power in Saigon under enemy siege flashed around the world, out of all proportion to its military importance. When these images were coupled with reports that the presidential palace, the radio station, and numerous other targets in Saigon had been attacked as well, President Johnson’s credibility evaporated. Public support for the war dropped twelve points between the “light at the end of the tunnel” public-relations campaign of the previous fall and the Tet Offensive.4 By late March, another poll revealed that 78 percent of Americans surveyed felt that the United States was not making any progress in the war, and only 26 percent of the American public approved of Johnson’s handling of the war. On March 31, 1968, President Johnson in a nationally televised speech indicated that he would not seek election to a second term. The enemy plan’s third assumption about American will had been correct.
The military effects of the Tet Offensive deserve more detailed attention because Americans in their opinion responses, and the increasingly acrimonious antiwar protests, never allowed either the Johnson or Nixon administrations to recover a wide base of popular support for the war. A historical understanding of events as they unfolded reveals a more complex narrative that became increasingly irrelevant to public opinion.
Reconstruction of the North Vietnamese plan for the Tet Offensive reveals that it was a classical deception plan borrowed from Chinese communist doctrine and the principles of Sun Tzu. One key element in the plan was a peripheral campaign designed to draw American and Vietnamese combat units out of the urban areas toward the borders of the country. On January 21, 1968, several NVA divisions converged on the isolated marine outpost at Khe Sanh in northern I Corps near the DMZ (maps 20.1 and 20.2). The NVA in attacking Khe Sanh was relying on the Americans to misread history and see the developing battle as another Dien Bien Phu in the making. This part of the deception worked—for a short time—until the Tet Offensive was launched nine days later. Khe Sanh drew the attention of most of the military and political leadership from Saigon to Washington. President Johnson’s attention was riveted on Khe Sanh. It became an obsession for him. He had a scale terrain model of the marine base built for the Situation Room in the White House.5
Map 20.2. The NVA divisions that attacked the marine outpost at Khe Sanh in I Corps were a response to the enemy’s strategic fear that the Khe Sanh position might be the start of a MACV strategy to block the Ho Chi Minh Trail.
Source: Based on USMC map and military unit data, dated 1968, hosted by Wikipedia Commons, http://en.wikipedia.org/wiki/File:KhSh9colkey.png.
Colonel Finlayson offers a more intriguing explanation for why the NVA attacked the marine base at Khe Sanh. During 1968, as a marine captain assigned to the Provincial Reconnaissance Unit in Tay Ninh Province, Finlayson worked closely with the CIA case officer for the “Tay Ninh Source,” who served as the highest-level US/GVN HUMINT penetration of the Central Office of South Vietnam (COSVN), the revolutionary movement’s headquarters in the South. The Tay Ninh Source had reported to the CIA that the North Vietnamese fear of an invasion of southern Laos was the main cause for their decision to attack the marine base at Khe Sanh and launch the Tet Offensive. An invasion of the Laotian panhandle, as Finlayson noted earlier, was the North Vietnamese leadership’s deepest strategic fear that the Americans might successfully block the Ho Chi Minh Trail by inserting sufficient forces into Laos.6
On January 2, 1968, a marine reconnaissance patrol spotted shadowy figures on the slope near the base’s outer defensive perimeter. The marines opened fire and killed six NVA officers. This incident convinced Westmoreland that several thousand enemy soldiers were near Khe Sanh and that they wanted to repeat their Dien Bien Phu victory at Khe Sanh against the marines. Westmoreland, who clearly was using the marines as bait to draw out the NVA units, saw this as an opportunity to fight a decisive engagement.
With this enemy buildup, the communists had cut Route 9, the only east–west line of communication to the coast. Westmoreland poured in supplies and reinforcements by air. Included on the flights into Khe Sanh were reporters eager for a big combat story. Their reporting elevated the Khe Sanh story out of all proportion to its strategic significance, as subsequent events showed. By mid-January, six thousand marines defended the main plateau and four surrounding hills named for their elevations—Hills 950, 881, 861, and 558 (map 20.2). Approximately half of the marine force defended the Khe Sanh base itself, and the remainder was deployed among the hill positions. Infantry at each garrison were supported by 105 mm howitzers, and the garrison could call on the prodigious airpower of 7th Air Force headquartered at Ton Son Nhut Air Base outside Saigon and the SAC B-52 wings based on Guam and in Thailand.
As brutal as the fighting at Khe Sanh became, the engagements fought over the next four months constituted neither the decisive battle that Johnson and Westmoreland expected nor a set-piece repetition of Dien Bien Phu in 1954. The battle commenced a week before Tet with the NVA 325thC Division launching an unsuccessful three-battalion assault on marine defensive positions outside the main firebase. Then, for the next three weeks, there was a seeming hiatus while the Tet Offensive raged throughout South Vietnam.
The marines at Khe Sanh effectively neutralized repeated NVA ground attacks, often after intense hand-to-hand fighting. Aid indicates that the SIGINT evidence shows that the NVA had to strip units from the front lines around Khe Sanh and send them south to support communist units mauled in fighting elsewhere. Aid judges Khe Sanh to be a SIGINT tactical success story rather than the decisive, strategic battle that General Westmoreland wanted and President Johnson needed to restore war policy credibility.7
Meanwhile, the communists had been using the Christmas 1967 cease-fire to move and mass their forces into position.8 At the same time, American SIGINT assets in late 1967 and early 1968 were intercepting increased radio traffic between NVA headquarters and subordinate combat formations, indicating that the enemy was preparing to attack cities in the Central Highlands (II Corps) and increase the pressure on Khe Sanh. None of these SIGINT reports were indicating any plans to mount a general offensive operation south of II Corps. At the same time that the National Security Agency (NSA)9 was reporting these intelligence developments in the north, a SIGINT station outside Saigon, the 303rd Radio Research Battalion at Long Binh, was reporting increased RF traffic much closer to Saigon. By mid-January, intelligence analysts were concluding that three NVA and VC divisions were now deployed in an arc around Saigon, within easy striking distance of the capital. Radio traffic between January 15 and 25, 1968, increased to an “almost unprecedented volume of urgent messages passing among major [enemy] commands.”10
NSA intercept sites in Southeast Asia continued to pick up further “hard” indicators that the North Vietnamese were about to be unleashed. One on January 28 revealed that “N-day” to launch the offensive was going to be January 30 at 0300. This message went straight to President Johnson. The Defense Intelligence Agency (DIA) discounted the imminence of these messages, believing that the Viet Cong would wait until the end of the Tet lunar holiday before commencing offensive operations. Then, a day later, on the night of January 29–30, 1968, as one radio-direction-finding post at Bien Hoa Air Base outside Saigon reported, every VC/NVA radio in the country went silent. As one army SIGINT specialist later recounted, “We could not raise a ditty bop for love nor money. It was the damnedest thing I never didn’t [sic, italics in original] hear. Complete radio silence.”11
Three hours later, one hundred thousand NVA and VC troops launched the massive and seemingly coordinated offensive against over one hundred cities, towns, and major military bases throughout South Vietnam, attacking thirty-eight of the country’s forty-four provincial capitals and seventy (of 250) district capitals, capturing Hue and seizing significant portions of Saigon. Although the communist plan included objectives nationwide, Saigon and the major US and ARVN bases in nearby Long Binh and Bien Hoa were important strategic objectives. This area, formed by a thirty-mile radius around the capital and known as the Capital Military Zone or Saigon Circle, was indeed strategic, but its symbolic significance was even larger in the collective mind of the American public. If Saigon was not secure, how could any place in the country be secure?
Fortuitously, Lieutenant General Frederick C. Weyand, commander of US II Field Force headquartered at Long Binh, had read the same NSA reports as MACV and did not like the pattern of increased enemy RF traffic reported in the Saigon area. In November 1967, troopers of the 101st Airborne Division had captured a communist document calling for a general offensive/uprising.12 While US intelligence analysts dismissed this along with the SIGINT reports on the grounds that it was beyond the capabilities of the enemy to launch a countrywide offensive, as most on the MACV staff believed, General Weyand convinced Westmoreland to let him pull more US combat maneuver battalions back in around Saigon. As a result, when the Tet Offensive broke, there were twenty-seven battalions instead of the planned fourteen in the Capital Military Zone to fight when the attack came. Weyand’s foresight significantly mitigated the damage caused by Tet in the Saigon area. Indeed, by mid-March, the number of US maneuver battalions around Saigon had increased to 152.13
Militarily, the Tet Offensive was a tactical disaster for the communists. By the end of March 1968, North Vietnam had not achieved its two principal military objectives, only to achieve something else, what proved to be the most crucial, the collapse of American public opinion about the war. However, on a hard-numbers reckoning, more than fifty-eight thousand NVA and VC troops died in the offensive. US military losses were 3,895 dead, with ARVN losses at 4,954. Non-US allies lost 214. More than 14,300 South Vietnamese civilians died. Most of the VC infrastructure that surfaced in many provinces was cut down or captured because VC guerrilla forces in the south in III and IV Corps led the major attacks and suffered the heaviest casualties. David T. Zabecki’s Tet entry in Tucker’s encyclopedia asserts flatly that “the guerrilla infrastructure developed over so many years was wiped out.”14 Lewis A. Sorley and others challenge Zabecki’s sweeping conclusion:
The fact that the Viet Cong infrastructure had remained largely intact after Tet 1968 was confirmed by continuation of the enemy’s ruthless campaigns of terrorism and assassination. More than a year later, the newly installed Nixon administration’s comprehensive survey of the situation in Vietnam15 also reached that conclusion.16
Elsewhere in the country, the Tet Offensive’s effects in the countryside weakened the GVN’s standing. Nearly five hundred of the five thousand paramilitary Regional Forces (RFs) and Popular Forces (PFs) outposts were abandoned or overrun. The government had to withdraw RF/PF units from rural hamlets into besieged cities and towns in many cases to provide additional defensive and blocking forces. More than 6,500 territorial forces soldiers were killed, were missing, or had deserted. The VC had attacked a number of Revolutionary Development Cadre (RDC) teams, and as a result the GVN had reassigned roughly half of the RDC teams, half of the ARVN battalions supporting them in pacification, and Vietnamese National Police and National Police Field Force units to help defend the cities. Most ARVN battalions resumed pacification duties at the end of February, but this relatively rapid resumption of the pacification mission was lost on any observer outside of MACV and its subordinate units.
Equally serious in the overall American perception was the malfeasance of some National Police and ARVN personnel. The most emblematic episode was the execution by Nguyen Ngoc Loan, director general of the National Police, of a handcuffed Viet Cong soldier on February 1, 1968, on a Saigon street in front of two witnesses, a Vietnamese cameraman working for NBC and an Associated Press photographer. The Pulitzer Prize–winning photograph would become one of the most recognized images of the war. Loan quickly became a one-man target for antiwar demonstrators, and more generally a representation of everything Americans at home feared about the Saigon regime: the impression of out-of-control violence, autocracy, corruption, and lawlessness.17
By the spring of 1968, it had become clear to the Johnson administration that the American people were no longer willing to accept the high casualty rates and open-ended commitment incurred by the armed forces of the United States in the Vietnam War. They averaged over three hundred Americans killed in action per week during 1968.18 No amount of nation building, it seemed to many critics dragging President Johnson down in the polls, could turn the situation around. The American strategic architecture to fight the Vietnam War had been broken by the nationwide violence of the Tet Offensive. Policy, strategy, and operations were perceived by the American public as wildly out of rational alignment. If American policy was to defend South Vietnam against a communist takeover by North Vietnam, and if the strategy was a combination of main-force military attacks against the NVA (by MACV and the ARVN) and COIN pacification in the countryside (by the GVN with CORDS), and if HES was showing light at the end of the tunnel, how could the Johnson administration explain the fighting countrywide that went on for months after Tet, especially when General Westmoreland had just requested 250,000 more troops?19