Answer:
China had become communist in 1949 and communists were in control of North Vietnam. The USA was afraid that communism would spread to South Vietnam and then the rest of Asia. It decided to send money, supplies and military advisers to help the South Vietnamese Government. The U. S. failed to recognize that the Vietnam was a civil war, and most of the wars in which we engaged--most notably WWI and WWII--were wars based on one country's domination over another so that was what made it
different then other wars.
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