For America, the greatest single controversy of the Second World War has always been the attack on Pearl Harbor. The success of the Japanese assault seared the psyche of the nation. How, with the United States reading the highest-level Japanese diplomatic codes, could the country be caught by surprise? How, despite a November 27, 1941, waning of imminent war with Japan, could the Pacific Fleet be found at anchor? How, despite the brilliant and heroic efforts of its gnome-like cryptanalysts, could the nation have been so unprepared? Some historians have argued that the answer lies with human failure, others that it rests with criminal conspiracy. In its fixation on self-flagellation, however, America has usually ignored another possibility: The answer may center not on what the Americans did wrong, but on what the Japanese did right.