0
Best Answer
The US formally entered WW 2 when the declared war on Japan (Public Law 77-328, 55 STAT 795) on December 8, 1841 - the day after the attack on Pearl Harbor. Japan's allies Germany and Italy declared war on the United States on 11 December 1941, bringing the US officially into the war in Europe as well.
Wiki User
∙ 6y agoThis answer is:
More answers
Wiki User
∙ 10y ago8 December 1941 - the day after the Japanese attack on Pearl Harbour
This answer is:
Add your answer:
Earn +20 ptsQ: When did the US join in world war 2?
Write your answer...
Submit
Still have questions?
Continue Learning about General History
Why did the US join the conflict of World War 2?
zoosk
What cause the US to join world war 2?
The Bombing of Pearl Harbor
Why did the us eventually join the world war 2?
Japan attacked us at Pearl Harbor, Hawaii
What year did the U.S. join Britain and France in World War 2?
The 8th of December 1941 was the date that the US joined world war 2
When did ameracia join World War 2?
1743
Related questions
Why did US not join World War 2?
The u.s did join WW2
When do the us join world war 2?
in 1956
When do US join World War 2?
in 1956
When the us join the world war 2?
The 8th of December 1941 was the date that the US joined world war 2
When US join World War 2?
They joined in1941
Which Ally did the US join in World War 2?
England
What side did the US join on the world war 2?
The Allies
Why did the US join the conflict of World War 2?
zoosk
What date did the US join World War 2?
joined in 1942
When did the us join the fighting in world war 2?
07 Dec 1941
What date did US join world war 2?
7 December 1941
What cause the US to join world war 2?
The Bombing of Pearl Harbor
Copyright ©2024 Infospace Holdings LLC, A System1 Company. All Rights Reserved. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Answers.