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 The U.S. 101st Airborne Division left South Vietnam, the last U.S. ground combat division to be withdrawn from South Vietnam.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
Peace treaty issues or separate treaties signed between each party. There are many possible issues which may be included in a peace treaty. Some of these may be: In modern times certain intractable conflict situations may first be brought to a ceasefire and are then dealt with via a peace process where a number of discrete steps are taken on each side to eventually reach the mutually desired goal of peace and the signing of a treaty. A peace treaty also is often not used to end a civil war, especially in cases of a failed secession, as it implies mutual recognition