Hitler begins an invasion of Russia, violating his own strategy against a two-front war. England survives defeats in Greece and Crete, but wins battles against the Italians in Libya until the Germans arrive. At the end of the year, suddenly attacked by the Japanese in the Pacific and the German U-Boats in the Atlantic, the United States joins the war.
War engulfs the Pacific when Japan attacks the United States Pacific Fleet at Pearl Harbor on December 7, 1941. Japan attacked the same day at Guam, Wake, Philippines, Singapore, and many other places. The Allies were not prepared for many reasons, including underestimating the size of the Japanese Army and transferring men and materiel to Europe and North Africa to fight the Germans. The Sino-Japanese War had expanded the war beyond China to the whole world.
Author of the World War II Multimedia Database