1972 in the Vietnam War the number of air raids against North Vietnam during all of 1971. Prime Minister Lon Nol declared President of Cambodia. Unlike the former Cambodian leader, Norodom Sihanouk, Lon Nol was a U.S. ally. The U.S. 101st Airborne Division left South Vietnam, the last U.S. ground combat division to be withdrawn from South Vietnam. The Khmer Rouge bombarded with artillery Phnom Penh, the capital city of Cambodia, killing more than 100 civilians. This was the heaviest attack on Phnom Penh since the Cambodian Civil War began in 1970. The United States boycotted peace negotiations in Paris with the North Vietnamese, citing
Anglo-Thai Peace Treaty Anglo-Thai Peace Treaty The Anglo-Thai Peace Treaty signed in Singapore on 1 January 1946 ended the state of war that had existed between Thailand and the United Kingdom since the former's declaration of war of 25 January 1942 during World War II. Although the Thais had also declared war on the United States on the same day, a U.S.–Thai peace treaty was never signed because the American government opted not to recognise the legality of the declaration in light of the Japanese invasion of Thailand on 8 December 1941. The peace treaty went into effect on the day it was