Between 1954 and 1968, the United States intervened in Vietnam, in an attempt to prevent a communist takeover of the country. There were a number of reasons why America chose to intervene. These included fear of communist expansion (the so-called Domino Theory), fear that the United States might look weak if it did not defend South Vietnam (the ‘demonstration effect’), the belief that victory could be secured through a series of small escalations (the so-called
‘slippery slope’), and fear of a domestic political backlash in the event of defeat.
South Vietnam was a creation of the United States – brought into being by the Eisenhower
Administration with the sole intention of preventing Ho Chi Minh from seizing all of Vietnam. At that time, world politics were seen entirely in the context of the Cold War – the ideological, political, economic and military struggle between the capitalist and communist worlds. As such,
Ho Chi Minh was seen by the US as an instrument of Soviet aggression, rather than a nationalist leader with strong domestic support. The US became convinced that a Vietminh victory would unleash a wave of communist revolutions across Asia – a view known as the Domino Theory. It remained a persistent theme in American decision-making throughout the Vietnam War.
Given this anti-communist fear, the US provided economic, political and military support to
Ngo Dinh Diem’s regime throughout the 1950s. Nevertheless, these efforts proved ineffective; the
Viet Cong grew in strength, and by 1961 its forces were threatening the very existence of South
Vietnam. Having devoted so much energy and so many resources to protecting its interests in this region, the Kennedy Administration was reluctant to accept defeat. Such an outcome would mean a significant loss of face, reducing the ability of the US to defend its interests in other, more vital, parts of the world. This so-called ‘demonstration effect’ explains why Kennedy sent 16,000 US advisers to South Vietnam, despite having reservations about the importance of the region to
America’s interests.
President Johnson faced a similar dilemma when he assumed office following Kennedy’s death in 1963. The US advisers had failed to stabilise the South. If anything, their presence only played into the Viet Cong’s hands, allowing them to portray the conflict as a struggle against foreign intervention. The situation continued to deteriorate until August 1964, when North Vietnamese gunboats fired on the USS Maddox , in retaliation against US raids on North Vietnam. Johnson portrayed the attack as unprovoked aggression, and had Congress pass the Gulf of Tonkin
Resolution, giving him the power to wage war as he saw fit.
Recently released tapes from the Oval Office make it clear that Johnson too had doubts about the importance of defending South Vietnam. However, he was very concerned that America might look weak if it failed to back its ally. As he put it, years later: “If I left that war and let the communists take over South Vietnam, then I would be seen as a coward and my nation would be seen as an appeaser, and we would both find it impossible to accomplish anything for anybody anywhere on the entire globe.”
Johnson was also concerned that his Republican opponents might exploit the conflict in Vietnam for political advantage, portraying him as weak in the face of communist aggression. He decided to silence them by initiating a bombing campaign against the North, allegedly in retaliation for the attack on the Maddox . This helped secure him the election in 1964, but it did not secure the South.
In January 1965, Johnson’s advisers recommended a round-the-clock bombing campaign against the North – Operation Rolling Thunder – as a means of persuading Ho Chi Minh to end his support for the Viet Cong. If anything, however, this had the opposite effect. Guerrilla attacks on
US airfields increased, forcing Johnson to deploy Marines to defend the bases. The first detachment of 3,500 arrived at Da Nang in March 1965.
These troops now found themselves under attack, and were soon given permission to conduct offensive operations against the Viet Cong. Of course, their numbers were insufficient for the new
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role they were assigned, and the ARVN was unable to offer meaningful support. The generals now informed Johnson that American ground troops would be needed, if defeat were to be forestalled.
Johnson could not countenance defeat, given the investment America had made in South
Vietnam over the preceding ten years, so he dispatched another 82,000 troops in July 1965.
Almost immediately the US military demanded more. By the end of the year, the number had grown to 120,000.
Johnson now found himself trapped into a cycle of escalation, with the military demanding more and more troops. By mid 1966, there were 300,000 in South Vietnam. By 1967, the number was half a million. It was as if America were on a slippery slope, falling deeper and deeper into war without any serious way out.
Hence, the decision by successive presidents to intervene in Vietnam can be explained by both international and domestic considerations. America’s leaders feared that if Vietnam fell to
Communism, the Domino Theory might come into play. This would threaten American interests in the region and be a blow to the nation’s credibility. They also feared that it might affect their political careers, leaving them with the blame for America’s first defeat in war.
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