Attack on Pearl HarborPearl Harbor was a very fierce attack by the Japanese against the United States. On December 7, 1941, Pearl Harbor, USA, was attacked by Japanese fighter planes. The United States had known about a possible attack since the 1920s; the United States became more involved when the Japanese invaded Manchuria. The attack on Pearl Harbor was the start of something big, a bloody war between the Japanese and the United States. The United States did not expect such an event; it was an unannounced attack on the naval base at Pearl Harbor, Hawaii. The unexpected attack on December 7, 1941 was originally only a pre-emptive effort to prevent the United States from interfering with military action the Empire of Japan was planning in Southeast Asia. Japan wanted to cripple the Pacific Fleet so as not to foil their plan to create a defense perimeter in the Southwest Pacific. Japanese planes launched two waves of air strikes sinking four U.S. Navy battleships and damaging two other battleships. The attacks also led to a high number of deaths. The original plan was to attack all US aircraft carriers. The attack on Pearl Harbor led to the entry of the United States into World War II. Japan had always been an ally of the United States. Japan tried to collect its share of treasure from Versailles. Japan had problems, Woodrow Wilson. Wilson rejected Japan's request for German concessions in Shantung. Duan Qirui, a Chinese warlord and politician, had borrowed money from Japan to strengthen the Chinese army. Japan used that loan and wanted it repaid by obtaining concessions in Shantung. In 1921, at the Naval Conference, the United States pressured Great Britain to end its 20-year alliance with the Japanese. Japan was now isolated, Stalin's unhappy empire to the north, in the center of the map, with so many troops and supplies, the Allied powers may not have won. The attack on Pearl Harbor was a very tragic event in the history of the United States. The Japanese continued to push North America's buttons. When the Japanese occupied Manchuria, which really scarred North America, it was a very bad move by the Japanese, FDR was not very happy with Japan's aggression against the Chinese. As a result, FDR froze all raw materials destined for Japan. Oil was the main export material going to Japan, its elimination really shook the Japanese economy. Japan actually planned and carried out the attack on Pearl Harbor. The United States was caught by surprise by the bombing. The United States was really shaken by the whole thing. We didn't expect something like this from the Japanese. The United States eventually joined the Allied forces during World War II. The United States actually taught the Japanese a lesson they needed to learn.