December 11th 1941: War !

The Japanese attack on the US naval base in Pearl Harbor, Hawaii, led President Franklin Roosevelt to declare war on Japan. A few days later, Nazi Germany declared war on the United States, and America entered World War II against the Axis powers.

On December 8th, 1941, one day after the attack on Pearl Harbor, the United States declared war on Japan. This prompted Germany to declare war on the United States, which, in turn, led to the United States to declare war on Germany on December 11, 1941. Responding to President Franklin Roosevelt.. 

On December 11th 1941, four days after the Japanese attack on Pearl Harbor and the United States declaration of war against the Japanese Empire, Nazi Germany declared war against the United States, in response to what was claimed to be a series of provocations by the United States government.