Vietnam War Withdrawal: The Final Battles
Withdrawal: The Final Battles U.S. Army
As the Americans withdrew, South Vietnam’s combat capability declined. The United States furnished its allies the heavier M48 tank to match the NVA’s T54 tank and heavier artillery to counter North Vietnamese 130mm. guns, though past experience suggested that additional arms and equipment could not compensate for poor skills and mediocre leadership. In fact, the weapons and equipment were insufficient to offset the reduction in U.S. combat strength. In mid-1968, for example, an aggregate of fifty-six allied combat battalions were present in South Vietnam’s two northern provinces; in 1972, after the departure of most American units, only thirty battalions were in the same area. Artillery strength in the northern region declined from approximately 400 guns to 169 in the same period, and ammunition supply rates fell off as well. Similar reductions took place throughout South Vietnam, causing decreases in mobility, firepower, intelligence support, and air support. Five thousand American helicopters were replaced by about 500. American specialties—B-52 strikes, photo reconnaissance, and the use of sensors and other means of target acquisition—were drastically curtailed.
Such losses were all the more serious because operations in Cambodia and Laos had illustrated how deeply ingrained in the South Vietnamese Army the American style of warfare had become. Nearly two decades of U.S. military involvement were exacting an unexpected price. As one ARVN division commander commented, “Trained as they were through combined action with US units, the [South Vietnamese] unit commander was used to the employment of massive firepower.” That habit, he added, “was hard to relinquish.”
By November 1971, when the 101st Airborne Division withdrew from the South, Hanoi was planning its 1972 spring offensive. With ARVN’s combat capacity diminished and nearly all U.S. combat troops gone, North Vietnam sensed an opportunity to demonstrate the failure of Vietnamization, hasten ARVN’s collapse, and revive the stalled peace talks. In its broad outlines and goals, the 1972 offensive resembled Bet 1968, except that the North Vietnamese Army, instead of the Viet Cong, bore the major burden of combat. The Nguyen-Hue offensive or Easter offensive began on 30 March 1972. Total U.S. military strength in South Vietnam was about 95,000, of which only 6,000 were combat troops, and the task of countering the offensive on the ground fell almost exclusively to the South Vietnamese.
Attacking on three fronts, the North Vietnamese Army poured across the demilitarized zone and out of Laos to capture Quang Tri, South Vietnam’s northernmost province. In the Central Highlands, enemy units moved into Kontum Province, forcing Saigon to relinquish several border posts before government forces contained the offensive. On 2 April, Viet Cong and North Vietnamese forces struck Loc Ninh, just south of the Cambodian border on Highway 13, and advanced south to An Loc along one of the main invasion routes toward Saigon. A two-month-long battle ensued, until enemy units were driven from An Loc and forced to disperse to bases in Cambodia. By late summer the Easter offensive had run its course; the South Vietnamese, in a slow, cautious counteroffensive, recaptured Quang Tri City and most of the lost province. But the margin of victory or defeat often was supplied by the massive supporting firepower provided by U.S. air and naval forces.
The tactics of the war were changing. Communist forces now made extensive use of armor and artillery. Among the new weapons in the enemy’s arsenal was the Soviet SA-7 hand-held antiaircraft missile, which posed a threat to slow-flying tactical aircraft and helicopters. On the other hand, the Army’s attack helicopter, the Cobra, outfitted with TOW antitank missiles, proved effective against NVA armor at stand-off range. In their antitank role, Army attack helicopters were crucial to ARVN’s success at An Loc, suggesting a larger role for helicopters in the future as part of a combined arms team in conventional combat.
Vietnamization continued to show mixed results. The benefits of the South Vietnamese Army’s newly acquired mobility and firepower were dissipated as it became responsible for securing areas vacated by American forces. Improvements of territorial and paramilitary troops were offset as they became increasingly vulnerable to attack by superior North Vietnamese forces. Insurgency was also reviving. Though their progress was less spectacular than the blitzkrieg-like invasion of the South, North Vietnamese forces entered the Delta in thousands between 1969 and 1973 to replace the Viet Cong—one estimate suggested a tenfold increase in NVA strength, from 3,000 to 30,000, in this period. Here the fighting resembled that of the early 1960’s, as enemy forces attacked lightly defended outposts and hamlets to regain control over the rural population in anticipation of a cease-fire. The strength of the People’s Self-Defense Force, Saigon’s first line of hamlet and village defense, after steady increases in 1969 and 1970, began to decline after 1971, also suggesting a revival of the insurgency in the countryside. Pursuing a strategy used successfully in the past, the North Vietnamese forced ARVN troops to the borders, exposing the countryside and leaving its protection in the hands of weaker forces.
Such unfavorable signs, however, did not disturb South Vietnam’s leaders as long as they could count on continued United States air and naval support. Nixon’s resumption of the bombing of North Vietnam during the Easter offensive and, for the first time, his mining of North Vietnamese ports encouraged this expectation, as did the intense American bombing of Hanoi and Haiphong in late 1972. But such pressure was intended, at least in part, to force North Vietnam to sign an armistice. If Thieu was encouraged by the display of U.S. military muscle, the course of negotiations could only have been a source of discouragement. Hanoi dropped an earlier demand for Thieu’s removal, but the United States gave up its insistence on Hanoi’s withdrawal of its troops from the South. In early 1973 the United States, North and South Vietnam, and the Viet Cong signed an armistice that promised a cease-fire and national reconciliation. In fact, fighting continued, but the Military Assistance Command was dissolved, remaining U.S. forces withdrawn, and American military action in South Vietnam terminated. Perhaps most important of all, American advisers—still in many respects the backbone of ARVN’s command structure were withdrawn.
Between 1973 and 1975 South Vietnam’s military security further declined through a combination of old and new factors. Plagued by poor maintenance and shortages of spare parts, much of the equipment provided Saigon’s forces under Vietnamization became inoperable. A rise in fuel prices stemming from a worldwide oil crisis further restricted ARVN’s use of vehicles and aircraft. South Vietnamese forces in many areas of the country were on the defensive, confined to protecting key towns and installations. Seeking to preserve its diminishing assets, the South Vietnamese Army became garrison bound and either reluctant or unable to react to a growing number of guerrilla attacks that eroded rural security. Congressionally mandated reductions in U.S. aid further reduced the delivery of repair parts, fuel, and ammunition. American military activities in Cambodia and Laos, which had continued after the cease-fire in South Vietnam went into effect, ended in 1973 when Congress cut off funds. Complaining of this austerity, President Thieu noted that he had to fight a “poor man’s war.” Vietnamization’s legacy was that South Vietnam had to do more with less.
In 1975 North Vietnam’s leaders began planning for a new offensive, still uncertain whether the United States would resume bombing or once again intervene in the South. When their forces overran Phuoc Long Province, north of Saigon, without any American military reaction, they decided to proceed with a major offensive in the Central Highlands. Neither President Nixon, weakened by the Watergate scandal and forced to resign, nor his successor, Gerald Ford, was prepared to challenge Congress by resuming U.S. military activity in Southeast Asia. The will of Congress seemed to reflect the mood of an American public weary of the long and inconclusive war.
What had started as a limited offensive in the highlands to draw off forces from populated areas now became an all-out effort to conquer South Vietnam. Thieu, desiring to husband his military assets, decided to retreat rather than to reinforce the highlands. The result was panic among his troops and a mass exodus toward the coast. As Hanoi’s forces spilled out of the highlands, they cut off South Vietnamese defenders in the northern provinces from the rest of the country. Other NVA units now crossed the demilitarized zone, quickly overrunning Hue and Da Nang, and signaling the collapse of South Vietnamese resistance in the north. Hurriedly established defense lines around Saigon could not hold back the inexorable enemy offensive against the capital. As South Vietnamese leaders waited in vain for American assistance, Saigon fell to the Communists on 29 April 1975.
The Post-Vietnam Army
Saigon’s fall was a bitter end to the long American effort to sustain South Vietnam. Ranging from advice and support to direct participation in combat and involving nearly three million U.S. servicemen, the effort failed to stop Communist leaders from reaching their goal of unifying a divided nation. South Vietnam’s military defeat tended to obscure the crucial inability of this massive military enterprise to compensate for Saigon’s political shortcomings. Over a span of nearly two decades, a series of regimes failed to mobilize fully and effectively their nation’s political, social, and economic resources to foster a popular base of support. North Vietnamese main force units ended the war, but local insurgency among the people of the South made that outcome possible and perhaps inevitable.
The U.S. Army paid a high price for its long involvement in South Vietnam. American military deaths exceeded 58,000, and of these about two-thirds were soldiers. The majority of the dead were low-ranking enlisted men (E-2 and E-3), young men twenty-three years old or younger, of whom approximately 13 percent were black. Most deaths were caused by small-arms fire and gunshot, but a significant portion, almost 30 percent, stemmed from mines, booby traps, and grenades. Artillery, rockets, and bombs accounted for only a small portion of the total fatalities.
If not for the unprecedented medical care that the Army provided in South Vietnam, the death toll would have been higher yet. Nearly 300,000 Americans were wounded, of whom half required hospitalization. The lives of many seriously injured men, who would have become fatalities in earlier wars, were saved by rapid helicopter evacuation direct to hospitals close to the combat zone. Here, relatively secure from air and ground attack, usually unencumbered by mass casualties, and with access to an uninterrupted supply of whole blood, Army doctors and nurses availed themselves of the latest medical technology to save thousands of lives. As one medical officer pointed out, the Army was able to adopt a “civilian philosophy of casualty triage” in the combat zone that directed the “major effort first to the most seriously injured.” But some who served in South Vietnam suffered more insidious damage from the adverse psychological effects of combat or the long-term effects of exposure to chemical agents. More than a decade after the end of the war, 1,761 American soldiers remain listed as missing in action.
The war-ravaged Vietnamese, north and south, incurred the greatest losses. South Vietnamese military deaths exceeded 200,000. War-related civilian deaths in the South approached a half-million, while the injured and maimed numbered many more. Accurate estimates of enemy casualties run afoul of the difficulty in distinguishing between civilians and combatants, imprecise body counts, and the difficulty of verifying casualties in areas controlled by the enemy. Nevertheless, nearly a million Viet Cong and North Vietnamese soldiers are believed to have perished in combat through the spring of 1975
For the U.S. Army the scars of the war ran even deeper than the grim statistics showed. Given its long association with South Vietnam’s fortunes, the Army could not escape being tarnished by its ally’s fall. The loss compounded already unsettling questions about the Army’s role in Southeast Asia, about the soundness of its advice to the South Vietnamese, about its understanding of the nature of the war, about the appropriateness of its strategy and tactics, and about the adequacy of the counsel provided by Army leaders to national decision makers. Marked by ambiguous military objectives, defensive strategy, lack of tactical initiative, ponderous tactics, and untidy command arrangements, the struggle in Vietnam seemed to violate most of the time-honored principles of war. Many officers sought to erase Vietnam from the Army’s corporate memory, feeling uncomfortable with the ignominy of failure or believing that the lessons and experience of the war were of little use to the post-Vietnam Army. Although a generation of officers, including many of the Army’s future leaders, cut their combat teeth in Vietnam, many regretted that the Army’s reputation, integrity, and professionalism had been tainted in the service of a flawed strategy and a dubious ally.
Even before South Vietnam fell, Army strategists turned their attention to what seemed to them to be the Army’s more enduring and central mission—the defense of western Europe. Ending a decade of neglect of its forces there, the Army began to strengthen and modernize its NATO contingent. Army planners doubted that in any future European war they would enjoy the luxury of a gradual, sustained mobilization, or unchallenged control of air and sea lines of communication, or access to support facilities close to the battlefield. France’s decision in 1966 to end its affiliation with NATO had already forced the Army to re-evaluate its strategy and support arrangements. The end of the draft in 1972 and the transition to an all-volunteer Army in 1973—a reflection of popular dissatisfaction with the Vietnam War—added to the unlikelihood of another war similar to Vietnam and made it seem more than ever an anomaly.
Instead, Army planners faced a possible future conflict that would begin with little or no warning and confront allied forces-in-being with a numerically superior foe. Combat in such a war was likely to be violent and sustained, entailing deep thrusts by armored forces, intense artillery and counterbattery fire, and a fluid battlefield with a high degree of mobility. Army doctrine to fight this war, codified in 1976 in FM (Field Manual) 100-5, Operations, barely acknowledged the decade of Army combat in Vietnam. The new doctrine of “active defense” drew heavily on the experience of armored operations in World War II and recent fighting in the Middle East between Arab and Israeli forces. From a study of about 1,000 armored battles, Army planners deduced that an outnumbered defender could force a superior enemy to concentrate his forces and reveal his intentions, and thus bring to bear in the all-important initial phase of the battle sufficient forces and firepower in the critical area to defeat his main attack. The conversion of the 1st Cavalry Division, the unit that exemplified combat operations in South Vietnam, from an airmobile division to a new triple capabilities (TRICAP) division symbolized the post-Vietnam Army’s reorientation toward combat in Europe. Infused with additional mechanized and artillery forces to give it greater flexibility and firepower, the division’s triple capabilities—armor, airmobility, and air cavalry—better suited it to carry out the tactical concepts of FM 100-5 than its previous configuration.
Yet the Army did not totally ignore its Vietnam experience. U.S. armor and artillery forces had gained valuable experience there in co-ordinating operations with airmobile forces. Although some in the military questioned whether helicopters could operate in mid-intensity conflict, Army doctrine rested heavily on concepts of airmobility that had evolved during Vietnam. Helicopters were still expected to move forces from one sector of the battlefield to another, to carry out reconnaissance and surveillance, to provide aerial fire support, and to serve as antitank weapons systems. In many respects, the role contemplated for helicopters in the post-Vietnam Army harkened back to concepts of airmobility originally formulated for the atomic battlefield of the early 1960’s, but modified by combat in Vietnam. Like the Army of the Vietnam era, the postwar Army continued a common hallmark of the American military tradition by emphasizing technology and firepower over manpower.
The Army’s new operational doctrine had its share of critics. Stressing tactical operations of units below the division, the doctrine of FM IOO-5 neglected the role of larger Army echelons. Recognition of this deficiency led to a revival of interest in the role of divisions, corps, and armies in the gray area between grand strategy and tactics. But some strategists warned that the Army seemed to be preparing for the war it was least likely to fight. Like the strategists of the New Look in the 1950’s, they viewed an attack on Army forces in Europe as a mere trip wire that would ignite a nuclear confrontation between the superpowers and thus make the land battle irrelevant. With insurgencies, small wars, subversion, and terrorism flourishing throughout Asia, Africa, and Latin America, others believed that that Army would sooner or later find itself once again engaged in conflicts that closely resembled Vietnam.
Ten years after the loss of South Vietnam, the U.S. Army’s major overseas commitments remained anchored in NATO and South Korea. International realities still compelled it to prepare for a variety of contingencies. In addition to organizing divisions to fight in Europe, the Army revived its old interest in light infantry divisions. By the mid-1980’s two such divisions, the 10th Mountain Division and the 6th Infantry Division (Light), had been activated, giving the Army once again a total of eighteen divisions. Lower active-duty strength required many divisions to be fleshed out by Reserve Components before they could be committed to combat. Nevertheless, the Army viewed its new divisions as suitable for use in a rapid deployment force to reinforce NATO or world trouble spots. Although their strength was drastically reduced following the Vietnam War, Special Forces continued to be called upon to advise and train anti-Communist military forces in Latin America and elsewhere and to participate in a variety of special activities to counter terrorism. Operations like the abortive attempt to rescue American hostages in Iran and the successful operation to prevent a Communist takeover of the Caribbean island of Grenada attested to the Army’s continuing need for both rapidly deployable and special-purpose forces. The realities of a complex world reinforced the pervasive influence of flexible response on the U.S. national security policy. Many other missions fell under the doctrinal umbrella of low-intensity conflict, a vague and faddish term that became popular in the 1980’s as counterinsurgency had two decades earlier. The relevance of Vietnam to low-intensity conflict remains an open question.
Nevertheless, by the 1980’s the conduct and lessons of the war in Vietnam had again become the subject of lively debate in the Army. Reassessments of its role tend to center around the issue of whether the Army should have devoted more effort to pacification or to defeating the conventional military threat posed by North Vietnam. These issues stem from the ambiguities of the war and the paradox of the Army’s experience. Reliance on massive firepower and technological superiority and the ability to marshal vast logistical resources have been hallmarks of the American military tradition. Tactics have often seemed to exist apart from larger issues, strategies, and objectives. Yet in Vietnam the Army experienced tactical success and strategic failure. The rediscovery of the Vietnam War suggests that its most important legacy may be the lesson that unique historical, political, cultural, and social factors always impinge on the military. Strategic and tactical success rests not only on military progress but on correctly analyzing the nature of the particular conflict, understanding the enemy’s strategy, and realistically assessing the strengths and weaknesses of allies. A new humility and a new sophistication may form the best parts of the complex heritage left the Army by the long, bitter war in Vietnam.