Japan was forced to bomb Pearl Harbor. The US desperately needed an excuse to join the war, so it cut Japan's oil supply from Venezuela. Japan was left two choices: to die by starvation or to die by war. Furthermore, the Americans KNEW the Japanese were going to attack and did nothing on purpose. Japan was kicking Chinese asses in the Sino-Japanese War, and destroying communism on that front. Even though many people don't like to admit so, US was supporting communism actively. After all, communism and capitalism are two faces o the same coin...
