Attack on Pearl Harbor in 1941, illustration. This US naval base on the island of Oahau, Hawaii, was attacked by the forces of Japan on 7 December 1941. Over 350 aircraft attacked in waves (red arrows) and damaged eight US battleships, sinking four of them. Other military facilities were also targeted. Over 180 US aircraft were destroyed and over 2400 people killed. The attack was carried out without warning as a pre-emptive strike by Japan. The attack was followed by Japan and the USA declaring war on each other, thus bringing the USA into World War II.