Greater East Asia War

Sanctions The economic sanctions imposed by the United States, Great Britain, and the Netherlands were weakening the Japanese economy. The leaders of Japan were faced with a choice: End the war in China, so as to end the sanctions, or obtain additional resources by some other means.

Attacking the Allies

The Japanese government decided to seize resources under the control of Great Britain and the Netherlands, notably in Malaya and the Netherlands Indies[?], with the Southern Expeditionary Army. As the United States was their ally, it was decided to attack the US Pacific Fleet at Pearl Harbor, Hawaii, with carrier-based aircraft of the Combined Fleet. Following this attack, the intended to seize the Philippines, as well as cut the US lines of communication by seizing Guam and Wake. At the same time they intended to attack Malaya and Hong Kong. This was to be followed by attacks against the Bismarck Archipelago[?], Java, and Sumatra. The Japanese then intended to go on the defensive and hold their newly acquired territory.

It is believed that the Imperial General Headquarters (Imperial GHQ) began planning the Greater East Asia War in April or May of 1941, by November their plans were essentially complete, modified only slightly over the next month. Japanese military planners argued that the British (and Russians should they decide to declare war) would be unable to effectively respond to a Japanese attack, given the threat posed by the Third Reich.

Contingencies

There is no evidence that the Japanese planned to defeat the United States, intending to negotiate for peace after it's initial victories. The Imperial GHQ noted that should acceptable negotiations be reached with the Americans, than the attacks were to be canceled, even if the order to attack had already been given. They also noted that should the US transfer it's Pacific Fleet to the Philippines, that they would intercept and attack this fleet enroute, with the Combined Fleet. The plans further stipulated that should the United States or Great Britain attack first, than the military was to hold and wait for orders from GHQ. Even should such a preemptive attack include Russia, the planners noted that attacking the Philippines and Malaya still had possibilities of success. See also:

• Military History
  • Military History of Great Britain[?]
  • Military History of Japan
  • Military History of the Netherlands[?]
  • Military History of the Philippines
  • Military History of the United States
  • World War II
    • Pacific Theater