Summary:
Pearl Harbor was a surprise attack by the Japanese Navy on the US naval base located in Pearl Harbor, Hawaii on December 7th, 1941. The attack was significant to the US war effort as it led to the US entering WWII, and the subsequent mobilization of the US armed forces.

Detailed Answer:
Pearl Harbor was a surprise attack conducted by the Imperial Japanese Navy against the United States naval base located in Pearl Harbor, Hawaii on December 7th, 1941. The attack, which lasted two hours, resulted in the destruction of four US Navy battleships, the sinking of three cruisers, the destruction of three destroyers, the sinking of 188 US aircraft, and the death of 2,403 US personnel and 68 civilians. The attack was significant to the US war effort for a variety of reasons. First, it forced the US into WWII, as the US declared war on Japan the following day. Second, it led to the mobilization of the US armed forces and the production of war materials, as the US had been largely isolationist prior to the attack. Finally, it galvanized public support for the war effort, as the US population was largely anti-war prior to Pearl Harbor.

Related Questions:

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