Final answer:
The attack on Pearl Harbor by Japan happened on December 7, 1941, which led to the United States entering World War II.
Step-by-step explanation:
Japan launched a sneak attack on Pearl Harbor on December 7, 1941. This action catapulted the United States into World War II following President Franklin D. Roosevelt's declaration of the date as \"a date which will live in infamy.\" The strike was meticulously planned as part of a larger effort by Japan to neutralize the United States as a Pacific power and enable the Japanese Empire to fortify its conquests in the region. On that fateful morning, the Japanese dispatched 353 aircraft from six carriers in two waves against the unprepared U.S. Pacific Fleet, resulting in the deaths of over 2,400 servicemen and significant damage to the fleet.
Fortunately for the U.S. Navy, its aircraft carriers were not in port and thus escaped destruction. The attack also led to subsequent declarations of war against Japan by the United States, and soon after by Germany and Italy, effectively broadening the conflict into a global war.
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