- The Axis powers are formed as Germany, Italy, and Japan become allies with the signing of the Tripartite Pact in Berlin.
- The Pact provided for mutual assistance should any of the signatories suffer attack by any nation not already involved in the war.
- Japanese planes attacked the United States Naval Base at Pearl Harbor, Hawaii Territory.
- The bombing killed more than 2,300 Americans.
- The attack sank a total of twelve ships and damaged nine others., 160 aircraft were destroyed, and capsized battleship U.S.S. Arizona and the U.S.S. Oklahoma.