The Allied leadership made operational changes and technological improvements of surface ships and planes far more rapidly than could the U-boats of the Kriegsmarine. America adapted to repair and produce aircraft carriers and train new crews at a pace inconceivable in Japan. The Allies--including the Soviet Union on most occasions--usually avoided starting theater wars that ended in multiyear infantry quagmires. In contrast, Japan, Germany, and Italy got bogged down respectively in China, the Soviet Union, and North Africa and the