The Vietnam war started as a result of U.S strategy of containment during the Cold War, which aimed to prevent the spread of communism throughout the world. The US had a policy to containment, to hold the communists to what they had without expanding, and they were also afraid that if Vietnam became communists, so would other nearby countries, falling like a series of domino's to the communists he Vietnam War was the prolonged struggle between nationalist forces attempting to unify the country of Vietnam under a communist government and the United States (with the aid of the South Vietnamese) attempting to prevent the spread of communism. Engaged in a war that many viewed as having no way to win, U.S. leaders lost the American public's support for the war. Since the end of the war, the Vietnam War has become a benchmark for what not to do in all future U.S. foreign conflicts.