American History — Recent American History · Question 91 of 128
Why did the United States enter World War II?
Practice answer: Because of the Japanese attack on Pearl Harbor
Why this is the answer
The United States entered World War II after Japan attacked Pearl Harbor, Hawaii, on December 7, 1941. Congress declared war on Japan the next day.
On the 2026 citizenship test, a USCIS officer asks up to 20 questions from the official 128-question pool — answering 12 correctly passes.
Study translations and question index
Practice index: 91. This is not the official 2025 syllabus question number. Translation indices share the same practice ID and answer-option order.
Español — practice:91:es
¿Por qué entró Estados Unidos en la Segunda Guerra Mundial?
Debido al ataque japonés a Pearl Harbor
العربية — practice:91:ar
لماذا دخلت الولايات المتحدة الحرب العالمية الثانية؟
بسبب الهجوم الياباني على بيرل هاربور
Official syllabus and legal sources
M-1778 (09/25) — 2025 USCIS syllabus. Retrieved 2026-10-15. Check current USCIS answers.
- 8 U.S.C. § 1423 — English, history and civics requirements
- 8 C.F.R. § 312.2 — Knowledge of history and government
These laws establish testing requirements; they are not individual legal advice or a citation for every historical answer. Practice questions and study translations are editorial learning aids, not official USCIS translations. Confirm the test version that applies to your filing date.
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