This attack came on the 7th of December 1941 when three Japanese aircraft carriers launched strikes against the American naval based as Pearl Harbor bring the USA into World War II. On the same day attacks were launched against several other targets in the South Pacific including the Philippines and Hong Kong, with Dutch East Indies being invaded a few weeks later securing the new source of oil.

In the following months Japan launched attacks across Asia and the Pacific conquering the Philippines, Dutch East Indies, Thailand, Burma, Singapore, Guam, Solomon Islands, Gilbert Islands, Marshall Islands, Wake Islands and taking half of New Guinea. Japanese forces were poised to expand even further towards India, Australia and even America itself.

In June 1942 the Japanese launched an invasion of the American island of Midway in the North Pacific, American forces had cracked the Japanese communication cyphers though and was waiting in ambush for the Japanese naval force. The battle that ensued is regarded as one of the greatest naval battles in history and the destruction of the Japanese fleet marked a turning point in the Pacific War against the Japanese.

After Japan's defeat the country was occupied by the Americans who disarmed and banned all military forces in the country, only a limited police was allowed to remain.

With the outbreak of the Korean War in 1950 and the threat of the conflict expanding into a possible third World War. It was felt that the small American occupation force in Japan wouldn't be enough to defend against a possible attack, so it was decided to allow the Japanese to rearm.

Article 9 of the Japanese Constitution however disallowed Japan from have any military forces. To get around this law though the newly created armed force was named the Japanese Self Defense Force which was officially established in 1954.