when did pearl harbor become a naval base
+ More. On Dec. 7, 1941, radios buzzed with the news that several hundred Japanese planes attacked a U.S. naval base at Pearl Harbor in Hawaii, killing more than 2,400 Americans as well as damaging or destroying eight Navy battleships and more than 100 planes. More. On Dec. 7, 1941, radios buzzed with the news that several hundred Japanese planes attacked a U.S. naval base at Pearl Harbor in Hawaii, killing more than 2,400 Americans as well as damaging or destroying eight Navy battleships and more than 100 planes.