In World War II, for the first time, the United States had to fight a war on two fronts. Though the central strategic principle governing allocation of resources to the two fronts provided for concentrating first on the defeat of the European Axis, on the American side this principle was liberally interpreted, permitting conduct of an offensive war against Japan as well as against Germany in the years 1943-45. The U.S. Fleet, expanding after its initial setback at Pearl Harbor much as the Army had, provided the main sinews for an offensive strategy in the Pacific, although the Army devoted at least one-third of its resources to the Pacific war, even at the height of war in Europe. In sum, the United States proved capable, once its resources were fully mobilized, of successfully waging offensives on two fronts simultaneously�a development the Japanese had not anticipated when they launched their attack on Pearl Harbor.
Japan's Strategy
Japan entered World War II with limited aims and with the intention of fighting a limited war. Its principal objectives were to secure the resources of Southeast Asia and much of China and to establish a "Greater East Asia Co-Prosperity Sphere" under Japanese hegemony. In 1895 and in 1905 Japan had gained important objectives without completely defeating China or Russia and in 1941 Japan sought to achieve its hegemony over East Asia in similar fashion. The operational strategy the Japanese adopted to start war, however, doomed their hopes of limiting the conflict. Japan believed it necessary to destroy or neutralize American striking power in the Pacific�the U.S. Pacific Fleet at Pearl Harbor and the U.S. Far East Air Force in the Philippines�before moving southward and eastward to occupy Malaya, the Netherlands Indies, the Philippines, Wake Island, Guam, the Gilbert Islands, Thailand, and Burma. Once in control of these areas, the Japanese intended to establish a defensive perimeter stretching from the Kurile Islands south through Wake, the Marianas, the Carolines, and the Marshalls and Gilberts to Rabaul on New Britain. From
