In 1965, U.S. combat troops were dispatched to Vietnam in support of the South Vietnamese, who were losing a lengthy civil war against Communist forces from North Vietnam. Despite a massive U.S. military presence (nearly 550,000 by 1969) and heavy bombing, they were unable to defeat the Viet Cong. America pulled out in 1973 after a peace agreement was reached, but this did not hold and South Vietnam capitulated in 1975. Over 50,000 Americans died in the conflict; South Vietnamese dead were estimated at more than 400,000, and Viet Cong and North Vietnamese at over 900,000