The surprise attack by the Imperial Japanese Navy on December 7, 1941, led the United States to declare war on the Empire of Japan, making the attack on Pearl Harbor the immediate cause of the United States' entry into World War II. government first obtained exclusive use of the inlet and the right to maintain a repair and coaling station for ships here in 1887. It is also the headquarters of the United States Pacific Fleet. Much of the harbor and surrounding lands are now a United States Navy deep-water naval base. with the signing of the Reciprocity Treaty of 1875. It was often visited by the Naval fleet of the United States, before it was acquired from the Hawaiian Kingdom by the U.S. Pearl Harbor is an American lagoon harbor on the island of Oahu, Hawaii, west of Honolulu. The USS Arizona Memorial is the small white dot on the left side above Ford Island
