Answer:
American believed in the "domino theory," that, if a country falls to Communism, then its neighbors are also likely to do so, mainly in the region of Southeast Asia. The United States involved in Vietnam by sent troops to help South Vietnam without engaging a war in the 1950s.
Answer:
The answer is: to help South Vietnam without committing US troops to a war
Explanation:
But what America didn't predict (or they predict, I believe), is that the interference in South Vietnam would become a conflict. After World War II, France left Vietnam and accepted it's asking for freedom. At that moment, Eastern Europe and some regions of Asia were under the communist influence zone (China introduced a communist regime in 1949). In the case of Vietnam, which was split into two parts (a capitalist, and a socialist/communist one), the problem was bigger. Somehow, the country didn't want to be separated, but be part of an influence zone, in this case, the Soviet zone. The threat of the communism be influent in so enormous territory (practically, a half part of the Asia continent, if we count China, the Korean peninsula, and Vietnam), America sent troops to South Vietnam to avoid an attach with the Soviet Union. Then, a war has begun.
