More than two thousand Americans were killed on December 7, 1941, almost half of them aboard USS Arizona. Military installations around the island were attacked, nineteen ships were sunk, beached, or badly damaged, and hundreds of Navy and Army planes were destroyed. In spite of this, the U.S. Pacific Fleet rebounded with remarkable speed as rescue operations soon evolved into a monumental salvage effort. Within a year, most of the ships damaged in the attack were returned to duty, and only USS Arizona, USS Utah, and USS Oklahoma were damaged beyond repair. Admiral Isoroku Yamamoto, planner of the attack, feared that the Japanese had awakened a sleeping giant and filled him with a terrible resolve. The day after the attack, Congress declared war on Japan, and in the course of that war, nearly all of the 31 Japanese ships of the Pearl Harbor strike force were sunk. Oil fires plagued USS West Virginia after she was sunk by aerial torpedoes, while USS Tennessee, also damaged, was moored alongside; Tennessee was repaired within two weeks, and West Virginia was raised, repaired, and returned to duty in 1944, later winning five battle stars and steaming into Tokyo Bay to witness the Japanese surrender.