History of Vietnam since 1945 unstable as no government could keep power for long. There were more coups, often more than one every year. The Communist-run Viet Cong expanded their operation and scored some significant military victories during this period. In 1965, US President Lyndon Johnson sent troops to South Vietnam to secure the country and started to bomb North Vietnam, assuming that if South Vietnam fell to the Communists, other countries in the Southeast Asia would follow, in accordance with the domino theory. Other US allies, such as Australia, New Zealand, South Korea, Thailand, the Philippines, and Taiwan also sent troops to South Vietnam.
Vietnam War were 543,000 American military personnel in Vietnam, but only 80,000 were considered combat troops." Conscription in the United States had been controlled by the president since World War II, but ended in 1973. As of 2013, the U.S. government is paying Vietnam veterans and their families or survivors more than $22 billion a year in war-related claims. By war's end, 58,220 American soldiers had been killed, more than 150,000 had been wounded, and at least 21,000 had been permanently disabled. The average age of the U.S. troops killed in Vietnam was 23.11 years. According to Dale Kueter, "Of those killed