This foreign policy is called “isolationism.” The United States believed in isolationism between World War 1 1914-1918) and WW2 (1941-1946) America had lost over 100,000 troops in WW1. When WWII started in 1939, Americans didn’t want to get involved in another European war. America eventually joined the Allies in 1941 after Hitler was winning in Europe and the Japanese bombed Pearl Harbor.
