What was roosevelts reason for entering the war?

President Franklin D. Roosevelt entered World War II primarily in response to the attack on Pearl Harbor by Japan on December 7, 1941. This surprise attack resulted in significant loss of life and damage to the U.S. Pacific Fleet, galvanizing public opinion in favor of war. Roosevelt aimed to protect American interests, support Allied nations, and ultimately defeat the Axis powers to ensure global stability and security. His famous speech the day after the attack emphasized the need for a strong response to aggression.