Why Did America Become Involved in Vietnam?

This section explores why America got involved with Vietnam. The United States’ involvement in Vietnam was driven by a combination of geopolitical concerns, fears of communism, and the desire to uphold its foreign policy commitments during the Cold War. Below are the key factors that led to America's intervention:

Key Facts on US Involvement

The Threat of Communist Expansion

The communist-backed Vietcong insurgents in South Vietnam posed a growing threat to the non-communist government, led by Ngo Dinh Diem. The Vietcong’s guerrilla tactics were highly effective, and the South Vietnamese government was struggling to maintain control. The rise of communism in the region was seen as a direct challenge to the spread of democracy and capitalism, which were central to US interests during the Cold War. The US, under its containment policy, feared that if Vietnam fell to communism, neighbouring countries in Southeast Asia could follow suit. This idea, known as the domino effect, became a driving force behind US involvement in Vietnam.

The Failure of US Support for the French

Prior to the involvement of US combat troops, the US had provided significant support to the French in their war to maintain control over Vietnam in the First Indochina War (1946–1954). The US gave millions of dollars in aid to the French military and sent military advisors to help train the South Vietnamese army. However, after the French were decisively defeated by the Viet Minh at the Battle of Dien Bien Phu in 1954, the US took a more active role. Although the US continued to support the anti-communist government of South Vietnam under Diem, the failure of these early efforts showed that financial aid and military advisors were insufficient to counter the growing communist insurgency.

The Assassination of Ngo Dinh Diem (1963)

In November 1963, South Vietnamese president Ngo Dinh Diem was assassinated in a coup carried out by his own military officers. His death led to political instability and the collapse of the South Vietnamese government. This power vacuum left the country vulnerable to further communist insurgency. For the US, this was a critical moment, as it could not afford to lose South Vietnam to communism. The US decided to step in to support a new government in an attempt to stabilise the situation and curb the communist threat.

The Gulf of Tonkin Incident (1964) 

In August 1964, an American naval vessel, the USS Maddox, was reportedly attacked by North Vietnamese torpedo boats in the Gulf of Tonkin, just off the coast of North Vietnam. Although the details of the attack were unclear and later questioned, the incident served as a catalyst for President Lyndon B. Johnson’s decision to escalate US involvement. The attack led Congress to pass the Gulf of Tonkin Resolution, which gave Johnson the authority to use military force in Vietnam without a formal declaration of war. This marked the beginning of full-scale American military intervention in the conflict.

The USA’s Tactics Under President Johnson

President Lyndon B. Johnson's strategy for Vietnam can be summarised by the acronym BEAST, which represents the key elements of the American military approach during his presidency.

Bombing (Operation Rolling Thunder) 

One of the most significant tactics employed by the US was extensive bombing campaigns aimed at crippling North Vietnam’s military infrastructure. The most notable bombing campaign was Operation Rolling Thunder, which began in 1965. The US targeted North Vietnamese air bases, supply routes, and the capital, Hanoi. By the end of the war, the US had dropped over 3 million tonnes of bombs on Vietnam, more than all the bombs dropped during World War II in Europe. However, the dense jungle environment and the lack of significant industrial targets made these bombings largely ineffective. The Vietcong were adept at hiding in the countryside, and the bombing led to considerable civilian casualties, further damaging the US’s image internationally.

Escalation of Ground Troops

Initially, the US sent military advisors to assist the South Vietnamese army, but by 1965, President Johnson began sending large numbers of combat troops. The first deployment of US Marines occurred at Da Nang, and by the end of 1965, 200,000 American soldiers were stationed in Vietnam. Over the following years, the number of US troops grew significantly, reaching over 500,000 by 1969. This escalation represented a shift from advisory support to direct combat involvement, with the aim of strengthening the South Vietnamese military and defeating the Vietcong.

Air and Artillery Support

American troops engaged in frequent patrols through the jungles and villages of Vietnam, often accompanied by air and artillery support. If the soldiers were attacked, airstrikes and artillery bombardments would follow to help suppress the enemy. However, this tactic had its drawbacks. Many soldiers felt demoralised, realising that they were being used as bait to lure the enemy out into the open where they could be destroyed from the air. This method of warfare also resulted in civilian casualties and significant collateral damage, contributing to the growing anti-war sentiment both in Vietnam and the United States.

Search and Destroy

One of the most controversial tactics used by the US military was the Search and Destroy strategy. This involved sending troops into villages and jungles in search of Vietcong fighters and their supplies. While this was intended to root out the enemy, it often led to civilian deaths and the destruction of homes. The Vietcong’s expertise in guerrilla warfare meant they could easily ambush US troops, making them vulnerable in the dense terrain. The high civilian toll and the resulting atrocities, such as the My Lai Massacre in 1968, significantly damaged the US’s reputation both domestically and abroad.

Technology

The US military heavily relied on advanced technology to conduct the war. Napalm, a highly flammable substance, was dropped from jets on suspected Vietcong strongholds, causing horrific burns and destruction. Agent Orange, a defoliant designed to destroy jungle cover, was sprayed extensively over large areas of Vietnam, harming the environment and causing long-term health issues for both the Vietnamese people and US veterans. Additionally, helicopters were used for troop deployment and to carry out search-and-destroy missions. Meanwhile, television propaganda in the US focused on body counts, presenting the war as a fight against communist forces and framing US involvement as necessary for global security.