Hitler's Biggest Blunder
Why did Germany declare war on the US in December 1941? Nicholas Henderson considers motives and consequences in the days before and after Pearl Harbor.
Hitler's declaration of war upon the United States of America on December 11th, 1941, four days after Japan's attack on Pearl Harbor, was a turning-point in history.
According to Ribbentrop, his foreign minister, and Ernst von Weizsaecker, State Secretary of the Foreign Ministry, Hitler believed that Germany and Italy were obliged to declare war under the terms of the Tripartite Pact. This had been signed with the Japanese in Berlin on September 27th, 1940. This was also the view of Goebbels according to the entry in his diary of December 9th:
We can have no other choice but to follow the letter of the law in the three-power treaty and declare war against the United States.