
The struggle against the Japanese in World War II led the United States to focus its attention on Asia, including Indochina. US involvement in Vietnam increased during the 1950s and 1960s, following the communist revolution in China and the rise of Ho Chi Minh and the Viet Minh.
US and the Viet Minh
In December 1941, Japanese planes attacked Pearl Harbour and Washington declared war on Japan. The Viet Minh was formed the same year to resist both the French and Japanese.
By 1944, agents of the Office of Strategic Services (OSS), the forerunner to the Central Intelligence Agency (CIA), were operating in southern China and northern Vietnam. These agents formed a working alliance with Ho Chi Minh and the Viet Minh, who assisted with safeguarding and repatriating American pilots downed over Vietnamese territory. In return, the OSS supplied Ho’s men with weapons and equipment.
It was an arrangement based on wartime expedience rather than political patronage. Nevertheless, Ho Chi Minh hoped that cooperating with the United States might lead to Washington’s support for an independent post-war Vietnam.
When Ho attempted to initiate Vietnamese independence in late 1945, he drew heavily on the United States’ own Declaration of Independence, citing its Enlightenment values of nationalism, popular sovereignty and self-determination. The Viet Minh leader hoped to demonstrate that his own political values were not far removed from those of the US.
The Domino Theory
After 1945, American involvement in Vietnam was driven and shaped by the Cold War. American foreign policy was largely shaped by the Truman Doctrine. Outlined in 1947, the Truman Doctrine argued that communism must be contained and governments susceptible to communist infiltration and takeover should be assisted. If this did not occur, communism would expand its global reach, taking root in one nation before jumping to its neighbours (the Domino Theory).
This was particularly relevant in Asia, where national governments were weaker and borders were poorly controlled. Asian nations, is was believed, had a lower capacity for resisting communist infiltration and invasion. Having spread from China to North Korea, American planners believed that communism would continue its movement further south to nations like Vietnam, Laos, Cambodia, Thailand, Burma, Malaya and Indonesia.
If these countries fell then communists would rule more than one-quarter of the globe – from East Germany to the shores of the Pacific Ocean. These fears were espoused by US vice president Richard Nixon, speaking in December 1953:
“Let us turn now to another area of the world: Indochina. And many of you ask this question: Why is the United States spending hundreds of millions of dollars supporting the forces of the French Union in the fight against communism in Indochina? If Indochina falls, Thailand is put in an almost impossible position. The same is true of Malaya, with its rubber and tin. The same is true of Indonesia. If this whole part of south-east Asia goes under communist domination or communist influence, Japan, who trade and must trade with this area in order to exist, must inevitably be oriented towards the communist regime. That indicates to you and to all of us why it is vitally important that Indochina not go behind the Iron Curtain.”
Washington backs the French

From 1947 the United States, determined to halt the growth of communism in Asia, backed the return of the French in Vietnam. This was not universally popular with Americans, many of whom despised colonialism and believed that Asian nations should be free to govern themselves.
In Washington, however, the revival of French colonialism in Indochina was seen a lesser evil than communist-ruled Vietnam. France, after all, was a democratic capitalist state and an important Cold War ally.
The Viet Minh, on the other hand, could not be trusted. The movement was riddled with communists and both its motives and political loyalties were unclear. The US considered Ho Chi Minh to be unreliable and possibly deceitful. He mouthed the slogans of a nationalist but Washington considered him a communist. There was some evidence to support this view, such as Ho’s work within the Soviet Union, the Comintern and the Chinese Communist Party.
US military aid increases
In late 1945, Washington’s formal position on Vietnam was vague but by early 1947, the US was tacitly supporting France. Later that year, US president Harry Truman authorised a moderate amount of funding ($160 million) to assist the French war effort. American administrators also turned a blind eye when Paris diverted some Marshall Plan funds to supply the war in Indochina.
By 1951, US military aid to the French had tripled to $450 million. By 1953, it was up to $785 million. French forces in Vietnam were using ships and aircraft on loan from the US. CIA agents were conducting covert operations in Vietnam in support of the French, like carrying out 700 supply drops to CEFEO troops trapped at Dien Bien Phu (1954).
By the time French forces surrendered to the Viet Minh in mid-1954, Washington had invested almost $3 billion in ‘saving’ Indochina from the spectre of communism.

The Geneva Accords
The French surrender at Dien Bien Phu and France’s withdrawal from Vietnam opened the way for greater direct US involvement. American delegates attended the Geneva conference of April-July 1954 but refused to sign the final agreement.
The Geneva Accords (1954) arranged for a two-year division of Vietnam until elections and reunification in 1956. The Americans preferred this temporary division become permanent. Washington wanted a nationalist, democratic state in the south to provide a buffer against communists further north.
Washington searched for an indigenous Vietnamese leader with pro-Western, anti-communist values to take charge in South Vietnam. They found a candidate in Ngo Dinh Diem, a minor political figure who had been living in North America since 1951.
American politicians and policymakers took a shine to Diem; he seemed exactly the person needed to lead South Vietnam and transform it into a bulwark against communism. In 1954, the US parachuted Diem into power, persuading Vietnamese emperor Bao Dai to appoint him prime minister. Diem was provided with massive American support: recognition, intelligence, money, trade deals, military equipment and training.
Failed nation-building
America’s mission in Vietnam now hinged on two things: Ngo Dinh Diem becoming a credible and effective leader, and North Vietnam accepting the north-south division of Vietnam.
By the end of the 1950s, it was clear that neither had occurred. The US government’s state-building program in South Vietnam had not succeeded. South Vietnam was largely a failed state, ruled by brutal nepotists and propped up by American aid. The South Vietnamese military had grown and developed considerably but was still incapable of defending the new nation.
Meanwhile, in Hanoi, the Lao Dong government was plotting to achieve reunification by stealth. In the late 1950s, communist insurgents unleashed a wave of terror attacks in South Vietnam, attacking government forces, facilities and figures. It was clear that a war between North and South Vietnam was imminent.
American policy in the 1950s and early 1960s attempted to shape and manage the situation in Vietnam without any direct US military involvement – but the worsening situation there, coupled with the arrival of a new president, brought a significant change in tactics.
A historian’s view:
“The US government became involved in Vietnam slowly. Each step of the way, for more than 20 years, policy-makers debated options, considered alternatives, and ultimately chose deeper involvement. By mid-1965, a series of incremental steps led to US ground troops facing combat in Vietnam. By 1968 the war had become a quagmire with no clear road to victory. Only in 1973, after laying waste to Vietnam and suffering massive casualties, would the United States ingloriously pull out the last of its troops. America’s longest war tore the nation apart.”
David R. Farber
1. The United States showed little interest in Vietnam until World War II when American agents worked with the Viet Minh against Japanese occupiers. Ho Chi Minh hoped this collaboration would convince the US to back Vietnamese independence.
2. After the war, Washington became concerned that Vietnam, among other Asian nations, was susceptible to communist infiltration and takeover. This view was informed by the Cold War, the Truman Doctrine and the Domino Theory.
3. Despite some misgivings about backing a colonial power, the US began to support the French in Vietnam. Washington aided the French during their war with the Viet Minh, investing almost $3 billion in the years prior to 1954.
4. The French withdrawal led to direct US involvement in Vietnam. The US did not sign the Geneva Accords and preferred to support the formation of a democratic South Vietnam, to serve as a buffer against communists in the North.
5. In 1954, the US parachuted Ngo Dinh Diem into the leadership of South Vietnam. American attempts to create a viable nation-state failed, and by the early 1960s, South Vietnam was at risk of infiltration and invasion by communists.
Citation information
Title: “US involvement in Vietnam”
Authors: Jennifer Llewellyn, Jim Southey, Steve Thompson
Publisher: Alpha History
URL: https://alphahistory.com/vietnamwar/us-involvement-in-vietnam/
Date published: June 19, 2019
Date accessed: September 25, 2023
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