Section: American History: Recent & Other

106. Why did the United States enter World War II?

Official answer

  • (Bombing of) Pearl Harbor
  • Japanese attacked Pearl Harbor
  • To support the Allied Powers (England, France, and Russia)
  • To oppose the Axis Powers (Germany, Italy, and Japan)

Why

The U.S. entered WWII after Japan's attack on Pearl Harbor in 1941.

Answers verified against USCIS materials. Last checked 2026-07-17.

Official source: USCIS — 128 Civics Questions and Answers (2025)