<P> Then the U.S. government gradually began supporting the French in their war effort , primarily through the Mutual Defense Assistance Act , as a means of stabilizing the French Fourth Republic in which the French Communist Party was a significant political force . A dramatic shift occurred in American policy after the victory of Mao Zedong 's Communist Party of China in the Chinese Civil War . By 1949 , however , the United States became concerned about the spread of communism in Asia , particularly following the end of the Chinese Civil War , and began to strongly support the French as the two countries were bound by the Cold War Mutual Defense Programme . </P>
why did the united states support the french war effort in vietnam
the Cold War Mutual Defense Programme