What is the current meaning of Japan's military power and what contribution has that power made to America's strategic position in East Asia, even the world, over the past fifty-five years? Could there have been an alternative to Japanese rearmament? Answers to these and other related questions lie in the American debates on the nature of Japan's defense situation in the immediate aftermath of World War II. Regional and global strategic circumstances have obviously changed over the past half-century, just as have weapons systems themselves. Strategic controversies from 1945, however, endure as the fundamental framework for considering Japanese military power and its possible alternatives.