Which side did the US support in the Chinese civil war and why during the cold war?

During the Chinese Civil War, the United States supported the Nationalist Party (Kuomintang) led by Chiang Kai-shek. This support was primarily motivated by the desire to contain communism, as the U.S. feared the spread of Soviet influence in Asia following World War II. The U.S. provided military and financial aid to the Nationalists, viewing them as a bulwark against the Communist forces led by Mao Zedong. However, this support ultimately did not prevent the Nationalists' defeat in 1949, leading to the establishment of the People's Republic of China.