The name of the policy that delayed U.S. entry into World War II was isolationism. Throughout the 1930s, many Americans favored a policy of isolationism, believing the nation should avoid involvement in foreign conflicts following the experiences of World War I. As tensions rose in Europe and Asia with the rise of fascism, isolationist sentiments remained strong until the attack on Pearl Harbor on December 7, 1941, which prompted a shift toward intervention. The policy of isolationism reflected a broader reluctance to engage in international affairs and shaped American foreign policy until it ultimately transformed into a commitment to global involvement following the entry into WWII.