A significant event that took place on December 7, 1941, was the surprise attack on Pearl Harbor by the Imperial Japanese Navy. This military strike targeted the United States' naval base in Hawaii and was intended to prevent American interference in Japan’s expansionist activities across the Pacific. The attack resulted in the destruction of numerous ships and aircraft, claiming over 2,400 American lives. This event was pivotal as it led directly to the United States' entry into World War II, dramatically shaping the course of the conflict and subsequent global geopolitics.