On September 28, 1940, Japan, Germany, and Italy signed the Tripartite Treaty. The treaty required the three nations to respond by declaring war if any of the other three nations was attacked by any of the Allied nations. Thereafter, if Japan attacked the United States, Americans would have a cause for war against Japan. If the United States responded by declaring war against Japan, the United States would thus be at war with Germany and Italy also.
December 7, 1941 - Japanese bomb Pearl Harbor.
December 8, 1941 - United States and Britain declare war on Japan.
December 11, 1941 - Germany and Italy declare war on the United States and sign new military alliance with Japan.
The maneuvering works just like the game. Roosevelt wanted war with Germany, but he needed a cause for war. Roosevelt had promised he would keep the United States out of war. There would be quite a loss of stability if there were a declaration of war against Germany without a cause. To get in the war, Roosevelt kept defenses low in the Pacific and did all that he could to provoke a confrontation. A CB is manufactured in a way and war is declared not on the nation of primary interest but on an ally who then brings Germany into the war. This is so much like EU2 tactics that it is scary.
