The attack on Pearl Harbor on December 7, 1941 came as a huge surprise to the United States, and led to a series of events that the world would never forget. Japan attacked Pearl Harbor because of worsening relations with the U.S. Three of the reasons are that Japan formed a Tripartite Agreement with Germany and Italy in the event of war, was invading Southeast Asia and China, and taking Chinese territory and natural resources because it couldn't support its 80 million person population on its own.
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