What actually cause them to join the war was the attack on Pearl Harbor
The proximate cause was Japan's attack on Pearl Harbor (December 1941). Following that, the US declared war on Japan and, in response, Germany and Italy declared war on the US.
US
Japan was at war in Asia, Germany was at war in Europe. Both of those countries were engaged in territorial conquests.
well of course we were at war with japan and china was on our side for the war too.
At the end of the war. or as a result of prisoner exchanges. or they escape. unles you upet the Americans then there is no real rule or any sort of ethic in volved.
Adolph Hitler a dictator of Germany in world war 2 declared war on the United States
The U.S before the time was bringing food to other countries and SOME war materials. After Pearl Harbor they began making more war materials and instead of giving food to other countries they began stockpiling for the army. U.S became very strained
After japan bombed pearl harbor the U.S entered the war and are the reason the war ended so soon and allies won
The main countries were Italy, Germany, Soviet Union, France, Great Britain, Japan, and after the attack on Pearl Harbor, America
When pearl harbor happened the USA decided that they needed to help the other allied countries fight in world war II!
US, Australia, New Zealand, Philippines, Thailand, S. Korea, S. Vietnam against North Vietnam and VC.