arrival

Worst Decision

2

Deployment of Combat Forces to Vietnam

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Introduction

On March 8, 1965, 3,500 Marines from the 9th Marine Expeditionary Brigade arrived in Da Nang, South Vietnam. Their mission was to protect a U.S. air base from attacks by the self-proclaimed National Liberation Front (NLF), the guerrilla force seeking to overthrow the South Vietnamese government that was better known to Americans by the pejorative name Viet Cong. Six days earlier, the United States had begun Operation Rolling Thunder, a bombing campaign against North Vietnam that would last for three years. Some U.S. officials opposed sending the Marines to Da Nang, predicting that President Lyndon B. Johnson would soon be pressed to send even more troops into a war that could not be easily won. Despite his own deep misgivings about the ability of the United States to win a conflict he called “the worst mess I ever saw in my life,” Johnson committed another 120,000 troops to South Vietnam over the next 5 months and more than a half million over the next three years. The war, however, remained unwinnable. SHAFR historians ranked the deployment of U.S. combat troops to Vietnam as the second-worst U.S. foreign policy decision.

The Domino Theory

A Communist-led insurgency led in 1954 to the end of French rule over Indochina and temporarily divided Vietnam into a Communist North and a non-Communist South. Fearing that if South Vietnam went communist the rest of Southeast Asia would follow—a belief known as the “domino theory”—the Eisenhower administration pumped economic and military aid into South Vietnam to position it as a counterweight to North Vietnam. That support included sending seven hundred U.S. military advisers.

In 1959, North Vietnam launched an insurgency in South Vietnam fought by the NLF. By the time President John F. Kennedy took office two years later, the insurgency had grown, exposing the South Vietnamese government’s weak popular support. Although Kennedy had argued years earlier that “no amount of American military assistance in Indochina” could defeat an insurgency that “has the support and covert appeal of the people,” he continued President Dwight D. Eisenhower’s commitment to South Vietnam and for the same reason. By the time of Kennedy’s assassination in November 1963, the U.S. presence in Vietnam had grown to sixteen thousand military advisors.

Map showing the division of North and South Vietnam, August 1964. Courtesy of the Naval Heritage and History Command.

The Gulf of Tonkin Resolution

South Vietnam was foundering when Johnson took office. The Kennedy administration had backed a coup against its deeply unpopular president, Ngo Dinh Diem. He was murdered in the coup, which was launched three weeks before Kennedy’s death. Although Johnson opposed the coup, he kept Kennedy’s national security team, most notably Secretary of Defense Robert McNamara. Johnson also doubled down on Kennedy’s anti-insurgency efforts.

Vietnam posed a political problem for Johnson. He was running for president in 1964 against Republican Barry Goldwater, who blamed him for failing to stop the insurgency in Vietnam. In August, Johnson responded to what he said were unprovoked attacks against two U.S. destroyers in the Gulf of Tonkin off the coast of Vietnam by ordering airstrikes against North Vietnam. He also convinced Congress to pass the Gulf of Tonkin Resolution, which authorized him “to take all necessary measures to repel any armed attack against the forces of the United States” not just in Vietnam but across Southeast Asia. Much of what the Johnson administration told members of Congress about the Gulf of Tonkin incident was untrue. Pledging to keep U.S. troops out of war in Vietnam, Johnson won the 1964 presidential election in a landslide.

We are not about to send American boys 9 or 10,000 miles away from home to do what Asian boys ought to be doing for themselves.

President Lyndon B. Johnson, October 21, 1964

Operation Rolling Thunder

Johnson said nothing about Vietnam in his inaugural address. He focused instead on remaking domestic policy by enacting Great Society programs like Medicare and passing the Civil Rights and Voting Rights Acts. But Vietnam remained a pressing issue. In early February 1965, NLF attacks killed thirty-one Americans. Johnson consulted with Eisenhower and Harry S. Truman; both former presidents urged him to hit back hard. Others that Johnson spoke to, including Vice President Hubert Humphrey, argued against deepening U.S. involvement in Vietnam.

Wedded to the belief “that when you give, the dictators feed on raw meat,” Johnson chose to escalate. Unwilling to invade North Vietnam because he feared triggering a war with China, Johnson quietly approved Operation Rolling Thunder, which sought to use a gradually intensifying bombing campaign against North Vietnam to boost South Vietnam’s morale while coercing Hanoi into ending its support for the NLF. Johnson also agreed to send 3,500 Marines to Da Nang to protect the U.S. airbase from attack. He chose escalation even though he told McNamara privately, “I don’t see any way of winning.”

An A-4 Skyhawk departs from the flight deck of the USS Coral Sea as part of Operation Rolling Thunder, March 24, 1965. Naval History and Heritage Command.

I guess we’ve got no choice, but it scares the death out of me. I think everybody’s going to think, ‘we’re landing the Marines, we’re off to battle.’

President Lyndon B. Johnson, March 6, 1965

President Lyndon B. Johnson meets with his senior national security advisors. April 28, 1965. Yoichi Okamoto / LBJ Library.

Some Carrots, More Sticks

In April 1965, Johnson offered North Vietnam carrots to go along with the stick of airstrikes. In a nationally broadcast speech at Johns Hopkins University, he offered to hold “unconditional discussions” with Hanoi and to invest $1 billion in Southeast Asia. A month later, he paused Operation Rolling Thunder for five days and privately offered to scale back U.S. attacks if North Vietnam eased its pressure on South Vietnam. Believing that battlefield trends were working in its favor and correctly suspecting that Johnson was looking to silence critics who said he was rushing into war rather than seeking serious negotiations, Hanoi dismissed both offers.

Meanwhile, Johnson felt growing pressure to use more sticks. Maxwell Taylor, the U.S. ambassador to South Vietnam and a former chairman of the Joint Chiefs of Staff, had warned Johnson in February that once U.S. combat troops arrived, “it will be very difficult to hold the line” on requests for reinforcements. Events proved Taylor right. In early June, General William Westmoreland, the head of U.S. military forces in South Vietnam, told McNamara that he needed 150,000 more troops. Johnson had reached a turning point.

Excerpts From President Lyndon B. Johnson’s Speech at Johns Hopkins University, April 7, 1965

“You Either Get Out or Get In”

Johnson complained privately about the demands that U.S. military leaders were making, saying at one point that they are “awfully irresponsible” and “ready to put a million men in right quick.” Some advisors urged Johnson to cut his losses. Undersecretary of State George Ball was the most vocal. He warned in early July that committing more troops to Vietnam meant “almost certainly a protracted war involving an open-ended commitment of U.S. forces, mounting U.S. casualties, no assurance of a satisfactory solution, and a serious danger of escalation at the end of the road.”

Most of Johnson’s advisors argued the opposite. General Earle Wheeler, the chair of the Joint Chiefs of Staff, said “no one ever won a battle sitting on his ass.” McNamara visited Saigon in early July and returned to say that committing more troops would “stave off defeat in the short run and offer a good chance of producing a favorable settlement in the longer run.” Johnson understood the stakes. As he told Senate Majority Leader Mike Mansfield, “it’s shaping up like this… you either get out or you get in.”

Phone Conversation Between President Lyndon B. Johnson and Secretary of Defense Robert McNamara on U.S. Options in Vietnam, July 2, 1965.

President Lyndon B. Johnson on the telephone in the Oval Office, July 17, 1965. Photo by Yoichi Okamoto / LBJ Library.

LBJ Escalates

Johnson doubted that sending more troops to Vietnam would produce victory. He told McNamara in early July that when he asked Congress to pass the Gulf of Tonkin Resolution, he “had no intention of committing this many ground troops. We’re doing so now, and we know it’s going to be bad.” But Johnson refused to turn back. Haunted by the memory of Europe’s appeasement of Hitler and by how Korea damaged Truman’s presidency, Johnson feared that failure in South Vietnam would derail his ambitious Great Society agenda and demolish his presidency. As he told his wife Lady Bird Johnson on the day he decided, “I don’t want to get into a war, and I don’t see any way out of it.”

Johnson decided to grant Westmoreland’s request. He brushed aside suggestions that he break the news by addressing a joint session of Congress or giving a nationally televised address. Not wanting to alarm the public or signal the immensity of his decision, he instead used a midday press conference on July 28 to announce that fifty thousand more troops were headed to Vietnam, adding that “additional forces will be needed later, and they will be sent as requested.” He also directed Westmoreland privately to use U.S. forces in Vietnam as he saw fit.

Secretary of Defense Robert McNamara and General Westmoreland, Vietnam Assistance Command Commander, with Vietnamese General Thi in August, 1965. National Archives.

President Lyndon B. Johnson’s Press Conference on Vietnam, July 28, 1965

The Legacy of the Decision to Commit U.S Combat Troops to Vietnam

Ball was right. The United States had 185,000 troops in Vietnam at the end of 1965. The total troop presence peaked at nearly 550,000 in 1968. As Johnson sent more troops, he consistently exaggerated the progress they were making. Then, in late January 1968, North Vietnamese and NLF forces launched the Tet Offensive, a surprise attack across South Vietnam. U.S. and South Vietnamese forces eventually turned back the attack, dealing a devastating blow to NLF forces in particular.

What Americans saw on their television screens, however, contradicted what Johnson had led them to believe. In the face of the public backlash, he abandoned his run for reelection. His successor, Richard Nixon, escalated the bombing of North Vietnam and waged a secret bombing campaign against neighboring Cambodia and Laos, which failed to change the tide on the battlefield. The United States signed a peace treaty with North Vietnam in January 1973. North Vietnam overran South Vietnam two years later. More than 58,000 Americans, and many more Vietnamese, died in the Vietnam War. The war Johnson chose to wage was unwinnable.

What Historians Say

  • Victor McFarland

    Victor McFarland

    The Vietnam War killed and injured millions of people, depleted U.S. resources, damaged America's image overseas, and inflamed political divisions at home. We're still living with the fallout.
    Associate Professor of History and Director of Graduate History Studies, University of Missouri
  • Jessica Chapman

    Jessica Chapman

    The deployment of combat forces to Vietnam marked the formal beginning of America's war in Vietnam, which cost both the U.S. and Vietnam an enormous toll in lives, ravaged the Vietnamese environment, contributed to the further radicalization of DRV leadership, fueled the rise of the genocidal Khmer Rouge, damaged American credibility and self-confidence, and emboldened the Soviet Union in the Third World.
    Sue and Edgar Wachenheim III Professor of History Chair, Williams College
  • Sheyda Jahanbani

    Sheyda Jahanbani

    The decision to send U.S. combat troops to South Vietnam cost Americans untold blood and treasure while also destroying U.S. credibility as a force for democracy and human rights.
    Associate Professor of History and Director of Graduate History Studies, University of Kansas
  • Joseph Steib

    Joseph Stieb

    The United States had reason to help the Republic of Vietnam resist communist aggression, but taking the primary military role for saving a faltering, corrupt autocracy was a massive strategic blunder. The war was immoral, unnecessary, and had shattering impacts on U.S. foreign policy and domestic politics.
    Assistant Professor of History, University of North Carolina at Chapel Hill

National Security Archive, GWU

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