ABCD Encirclement

The ABCD encirclement (ABCD包囲網, Ēbīshīdī hōimō) was a series of embargoes against the Empire of Japan by foreign nations, including the Americans, the British, the Chinese, and the Dutch. In 1940, in an effort to discourage Japanese militarism, these nations and others stopped selling iron ore, steel, and oil to Japan, denying it the raw materials needed to continue its activities in China and French Indochina. In Japan, the government and nationalists viewed these embargoes as acts of aggression; imported oil made up about 80% of domestic consumption, without which Japan's economy, let alone its military, would grind to a halt. The Japanese media, influenced by military propagandists, began to refer to the embargoes as the "ABCD ("American-British-Chinese-Dutch") encirclement" or "ABCD line". Faced with the possibility of economic collapse and forced withdrawal from its recent conquests, the Japanese Imperial General Headquarters began planning for a war with the Western powers in April 1941. This culminated in the Japanese invasion of Malaya and Thailand, and the bombing of Pearl Harbor in December 1941.