Abstract
This thesis evaluates American intelligence assessments of Japanese air and naval power during the interwar period. All issues from the assessment of personnel, tactics and technology, to strategy and industry are addressed together. American assessments of Japan’s poor strategic and industrial position remained highly accurate, while assessments of Japanese tactics and technology were flawed. Since the Americans planned to fight a prolonged war of attrition, strategic and industrial assessments proved far more critical than those which assessed low level issues. Their conclusion was that Japan could not win a war against the United States. Errors in the assessments of Japanese technology and tactics contributed to the shock and embarrassment of the early defeats in the Pacific War, but were not the main cause of those defeats. The underestimation of Japanese air power did more damage to the Americans than the middling assessments of Japanese naval power.
