America's full-scale military involvement in Vietnam

The Gulf of Tonkin Incident

The Gulf of Tonkin incident occurred when North Vietnamese boats allegedly attacked American naval vessels in the Gulf of Tonkin.

During the incident, North Vietnamese torpedo boats were seen approaching a US ship. As a result, the US fired three warning shots. Allegedly, the boats attacked and fired torpedo shots which Maddox evaded. When they continued to approach, Maddox, the US ship, fired on them. It resulted in major damage to the North Vietnam torpedo boats and the deaths of some on board while the US ship Maddox received minor damage and zero casualties or injuries.

In reaction to the Gulf of Tonkin Incident, the Gulf of Tonkin Resolution was passed by congress, allowing the President to do anything to assist "any member or protocol state of the Southeast Asia Collective Defense Treaty", including the use of armed forces.

What types of warfare were used in the Vietnam War?

Both the US Army and the Viet Cong used military tactics and the types of warfare that they implemented were influenced by the level of support from the local population and the level of motivation and commitment from their soldiers.

See here for a brief look at the types of warfare that were used in the Vietnam War.

Following the Gulf of Tonkin Resolution, the United States began to significantly increase its military presence in Vietnam. 

Operation Rolling Thunder

The United States launched a sustained bombing campaign, codenamed Operation Rolling Thunder, against North Vietnam in 1965.

Operation Rolling Thunder began on March 2, 1965, following the passage of the Gulf of Tonkin Resolution, which granted President Lyndon B. Johnson broad powers to use military force in Vietnam. The key targets of the operation were military bases, airfields, transportation networks, industrial facilities, and other strategic infrastructure in North Vietnam. The campaign aimed to degrade North Vietnam's ability to support the communist insurgency in South Vietnam led by the Viet Cong, and was characterized by a sustained and escalating level of bombing over three years. The campaign involved both conventional bombing raids by aircraft, including B-52 bombers, and the use of naval bombardment from US Navy warships in the Gulf of Tonkin.

Instead of pressuring North Vietnam into ceasing its efforts of supporting the Viet Cong and capturing South Vietnam, it strengthened the resolve of communist forces and fueled anti-American sentiment due to the extensive damage to Vietnamese infrastructure and impacts on the civilian population. 

Ground Operations

In 1965, President Johnson ordered the deployment of ground combat troops to Vietnam, marking the beginning of a major escalation of US involvement in the conflict. Ground operations, such as Operation Junction City and Operation Cedar Falls, aimed to disrupt enemy supply lines, locate and destroy Viet Cong bases, and gain control over strategic areas.

Tet Offensive

When the Viet Cong and North Vietnamese forces launched the Tet Offensive on 30th January 1968, targeting key urban centres, government buildings, military installations, and major population centres in more than 100 cities, towns, and military installations across South Vietnam, it marked a turning point in the Vietnam War. 

The offensive shattered the perception of American and South Vietnamese military superiority, shocked the American public, undermined confidence in the US government's handling of the war, and led to a reassessment of US strategy in Vietnam. 

Nevertheless, the Tet Offensive ultimately ended in military defeat for the Viet Cong and North Vietnamese forces.