The attack on Pearl Harbor was an attempt by Japanese forces to destroy as much of the U.S. Pacific Naval Fleet as possible. Its purpose was two-fold: (1) Prevent U.S. interference with Japanese operations in the Pacific Basin, and (2) Hopefully resolve any outstanding issues with the U.S. before the Atlantic Fleet could be deployed to the Pacific.
The Japanese commander responsible for the attack was Adm. Isoruku Yamamoto. He had studied at Harvard, and was fluent in English; Yamamoto had a low opinion of the U.S. Navy, stating that its officer corps was primarily golfers and bridge players. It was he who suggested the attack be staged on a Sunday morning, as this was a day of relaxation for most Americans, and they would more easily be caught off guard. A Japanese spy living in Hawaii took pictures of all ships in the harbor days before the attack, and forwarded these to Tokyo, so the Japanese pilots knew the location of every capital ship prior to the attack. Chief pilot for the attacking force was Mitsuo Fujida.
The fleet carrying the attack force left Tokyo on November 26, 1941. The attack commenced at 8:00 a.m. December 7. The first wave of bombers attacked Hickham Field air base to prevent American planes from defending. They received unintended help from the American commander of Hickham Field, as he feared sabotage more than an air attack, and had the aircraft parked close together. The result was several planes could be taken out with one bomb.
Although there is some argument to the contrary, most evidence suggests that the Japanese had planned to deliver a formal declaration of War to Secretary of State Cordell Hull thirty minutes before the attack commenced; however because of delays, Hull did not receive the message until the attack was underway. Hull was aware of the attack when he met with the Japanese ambassador.
A number of ships were destroyed, including the USS Arizona and the USS Utah; however many capital ships, including the Aircraft Carriers had been deployed at sea, and thereby escaped damage. Although a third wave of attacks had initially been planned, Yamamoto decided against it. For this reason, many of the docks and land facilities at Pearl Harbor remained in tact. As a result of the attack, four ships were sunk and four others damaged. One hundred eighty eight aircraft were destroyed, 2402 Americans killed and 1282 wounded.
American commanders at Pearl Harbor anticipated that the attack was the prelude to an invasion, but no invasion occurred. The American naval commander, Adm. Husband Kimmel committed suicide after the attack; even though substantial evidence indicated it was beyond his control. After Kimmel's death by suicide he was posthumously exonerated from all responsibility.
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