Attack on Pearl Harbor
In mid-1940, President Franklin D. Roosevelt moved the Pacific Fleet from San Diego to Hawaii. He also ordered a military buildup in the Philippines. He hoped that taking both actions would stop Japanese aggression in the Far East. The Japanese thought attacking the United Kingdom would mean they had to attack the United States. Japan then decided they would have to launch a massive attack on the US. An invasion of the Philippines was also considered necessary by Japanese war planners. The U.S. War Plan Orange called for defending the Philippines with an elite force of 40,000 men. This option was never done because Douglas MacArthur didn't like it. He thought he would need a force ten times that size. By 1941, U.S. planners expected to abandon the Philippines at the outbreak of war. Late that year, Admiral Thomas C. Hart, commander of the Asiatic Fleet, was given orders to that effect.