What significant event occurred on December 7th, 1941?

December 7th, 1941, is historically significant because it marks the attack on Pearl Harbor by the Imperial Japanese Navy. This surprise military strike led to the United States' entry into World War II, fundamentally changing the course of the war and global politics at the time. The attack resulted in significant loss of life and damage to the Pacific fleet, catalyzing a unified response from the American public and government, which had previously been divided on the issue of entering the war. Following this event, the United States declared war on Japan on December 8th, 1941, which subsequently led to its involvement in the broader conflict against the Axis powers.