On 7 December, 1941, there was a surprise attack by the Japanese airforce on the United States navy base at Pearl Harbor in Hawaii. Although the attack crippled the US Navy in the Pacific Ocean, it also drew the Americans into World War II.
The USA and its Allies declared war on Japan on 8 December, 1941. Japan joined Germany and Italy to form the Axis alliance. During the summer of 1942, US forces successfully halted the Japanese advance at the battles of Midway Island, Guadalcanal and Coral Sea.
After Pearl Harbor, however, Japanese forces quickly took control of much of Southeast Asia, including Singapore, Burma and the Philippines.