Question: why did the united states wait until 1941 to enter world war ii?
Answer: WHY DIDN'T THE USA JOIN WWII IN 1939? World War II began in September of 1939 when both Britain and France declared war on Nazi Germany followings its invasion of Poland. ... The United States would not join the Allied war effort until 1941 when it was attacked by the Japanese Empire in Pearl Harbor on December 7th.