AfterThe Second World War ended, the US dispatched George C.Marshall to China, continued to mediate the Kuomintang and Communist Parties civil war; Not long time, Kuomintang and Communist Parties strength fit and unfit. In August, 1949, the US published ”The China White Paper”-losed mainland China the responsibility pushed for the Chinese government leader Chiang Kai-Shek. President Truman based on its national interest, before the publication ”the white paper” in April, namely life diplomatic agent John Leighton Stuart stationed in China, tried to contact, established diplomatic relations with the Chinese Communist Party.This involvement-The Chinese business's policy toward China, affected Republic of Chinas' national security to be really great, even caused China changed that the Communist Party established People's Republic of China.