Kennedy approved the removal of the now hated Diem and his family, though he was shocked when the coup resulted in their deaths. The coup was a strategic error, creating a period of instability and the NLF quickly took advantage. US forces were increased to 16,000 as Kennedy sought a way to regain control.
The assassination of President Kennedy was followed by President Johnson, who saw Vietnam as a distraction from his domestic priorities. A pair of controversial attacks on USN warships in the waters off Vietnam was used to increase the US commitment to the war. The first of these two attacks certainly took place, and the missile boats are in Vietnamese museums. The second attack may have been a radar error, and remains controversial to this day. Lyndon B. Johnson used these to force a major increase in forces committed, unwilling to be seen as the President who lost the war.
The US started a major bombing campaign against the north to encourage it to stop supporting the NLF, and began increases of military forces committed until US troops topped half a million. Additionally, Filipino, Thai, Australian, New Zealand and Korean troops also fought for the south.
President Johnson had a very secretive policy and this lack of candour hurt his policy with the US public. Current scholarship is reexamining conventional wisdom about the role of the anti-war movement, but at the time it was seen as a major theatre of conflict and a vital means to defeat US involvement in the war. The traditional American weakness in Information Operations was well evident during the whole conflict.
The Tet Offensive
In January of 1968 the NLF attacked Khe Sanh in the Demilitarised Zone in what proved to be the biggest battle of the whole war. Some 10,000 North Vietnamese were killed as well as around 500 US soldiers. It proved to be a diversionary tactic from what was to take place a week later, the Tet Offensive.
On the night of January 31st, whilst the country was celebrating the Lunar New Year, the Viet Cong started an enormous offensive on towns and cities all over South Vietnam including Saigon where the courtyard of the US embassy was briefly occupied. US and South Vietnamese forces hit back with huge firepower which caused huge losses of VC personnel and civilians. Around 3000 members of the Army of the Republic of Vietnam (ARVN) and US troops lost their lives as a result of the Tet Offensive whilst more than 30,000 VC troops were killed.
Whilst US military chiefs claimed a great victory, the shocked media back in the US portrayed it as a stunning US defeat having seen events unfold on their TV sets. As a result, public opposition to the war back in the US reached an all time high. In spite of enormous VC casualties, the Tet Offensive ultimately proved to work in their favour. Antiwar demonstrations in the US became even more widespread as reports of atrocities against Vietnamese civilians became public such as the My Lai Massacre.
Final Years of the Vietnam War (1969-75)
One notable casualty of the Tet Offensive was the presidency of Lindon Johnson who was succeeded by President Nixon who was elected in no small part to put an end to the war. When elected, he didn’t know how he was going to do this, but his staff quickly put together the Vietnamization program. US units would gradually turn over missions to the ARVN which would be greatly strengthened and trained. As part of this comprehensive restructuring, the government of Cambodia under Sihanouk was forced to abandon their claims of neutrality while sheltering People’s Army of Vietnam forces on his soil, and Nixon ordered secret bombing raids on those extranational sanctuaries. Sihanouk was deposed, and the Khmer Rouge were able to take advantage of the instability. Cross border ground operations took place, and were followed by Vietnamese led incursions into Laos which served as a sanctuary for the People’s Army of Vietnam (PAVN).
US forces continued to draw down, and fell to less than 200,000 in 1971, with more reductions scheduled. 1972 saw overt invasion from the north. US airpower provided the edge needed to defeat the Easter Invasion. Another US aerial attack was used to force the north to negotiate the Paris Peace Accords. US military forces were essentially removed after this, as required within 60 days. This was the only part of the treaty that actually took place.
In 1975, the north again attacked, with more tanks than the Wehrmacht used to invade France in 1940 and more trucks than Patton’s Third Army. The critical US logistical and air support was denied. President Thieu panicked, and issued a series of conflicting orders to his forces, which collapsed in the face of the invasion.
The Republic of Vietnam fell on 30th April 1975, right after Cambodia fell to the Khmer Rouge and months before Laos fell to the Pathet Lao.
In Vietnam, hundreds of thousands were imprisoned by the new leadership, with tens of thousands killed. Two million fled the country. Two million died in Cambodia alone, almost a third of the population, killed by the Khmer Rouge. In 1995, Hanoi admitted that four million civilians died in the war, north and south, and over a million Vietnamese soldiers. US forces suffered 58,000 dead.