 After the United States joined the war against Japan in 1941, American politicians and military advisors became increasingly interested in making contact with the Communists in order to coordinate attacks on the Japanese.In June 1944, Chiang Kai-shek agreed to allow an American military observation group, known as the "Dixie mission", to travel to Yan'an.Mao and Zhou welcomed this mission and held numerous talks in the interest of gaining access to American aid.