Question

What factors led to the united states entering world war 2?

Answer 1

The bombing of Pearl Harbor and Churchill saying he'll give up to the Nazis if the US doesn't help them, post haste. 

Answer 2

Answer:

The event that led to the United States entering World War II was the Japanese bomb attack of the Pearl harbor in Hawaii. This attack demanded U.S. entry into the war to defeat the aggressors.