Allied Defeats and the Axis
The losses at Pearl Harbor marked the beginning of the darkest period in American military history. For the next six months the United States and its allies suffered defeats and retreated before superior Axis forces. The Axis powers controlled the greater parts of the European and Asian continents, North Africa, and the islands of the western Pacific, and they dominated the Pacific, Atlantic, and Indian oceans. Never before had Americans been so threatened and insecure as in the enemy-dominated world of the last weeks of 1941 and the early months of 1942.
Germany exploited its advantage on three fronts: the Battle of the Atlantic against the British and American navies; the struggle in North Africa against the British army; and the war on the vast Eastern Front against the Soviet Union.
In waging the naval war, the German U-boat (submarine) campaign took a staggering toll of the shipping essential to the