The Battle of Midway, a decisive engagement of World War II in the Pacific, was also of major importance in naval history. Following the precedent set in the Battle of the Coral Sea, Midway was fundamentally an air action. Japan's objective was to extend her eastern frontiers through the seizure of the Midway Atoll, and decisively to engage the American Navy under conditions favoring Japan, with the Aleutians operation as a diversion posing a threat to Alaska. The United States intent was to end the Japanese threat to Hawaii and Japan's offensive action in that area and to reestablish the balance of naval power in the Pacific. The outstanding American naval strategical and tactical victory confirmed the Allied concept, while Japan's heavy losses forced her to adopt a defensive role and to change her fleet organization, emphasizing carriers over battleships.