Three Causes for American Involvement in World War II. Three causes for American involvement in World War II will be examined in this paper. The attack on Pearl Harbor, the rise of Hitler and the Holocaust will be the three leading reasons why America entered the war and won it. 5 pgs. Bibliography lists 7 sources. Pages: 5 Bibliography: 7 source(s) listed Filename: 4111 Causes American Involvement.doc Price: 44.75