Second World War - Pacific Ocean
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The unheralded - though not exactly unexpected - Japanese attacks on the island archipelagos of the Pacific Ocean from 8 December 1941 onwards introduced the Pacific as one of the main theatres of action in the Second World War. When 360 Japanese planes sank three US battleships, three cruisers and three destroyers at the Pearl Harbor anchorage in Hawaii on 8 December, they dragged the United States formally into the war and ensured - ultimately - their own destruction. The 'instant empire' that Japan, poor in natural resources, had so daringly acquired melted away after three years of savage and very bloody war at sea and on the islands of the Pacific.

The Royal Navy’s Eastern Fleet, the Royal Indian Navy and the Indian Air Force were fully occupied in the Indian Ocean, in Burma and in the waters and air space around India, providing naval and air support for a large variety of Allied operations against the Japanese. The IAF was to win 1 DSO, 21 DFCs (one with a bar), 2 AFCs and 45 Mentions In Despatches. Those serving with the RIN won 8 DSCs, 23 DSMs and 62 Mentioned In Despatches. Operations in the Pacific Ocean and its island chains were largely the responsibility of Australian and US forces.
Two crew of HMIS Narbada cleaning a twin Oerlikon gun
Two crew of HMIS Narbada cleaning a twin Oerlikon gun
© Imperial War Museum

On 10 December 1941 the Japanese took Guam Island, on 23 December Wake Island - both important strategic bases. From January to March 1942 they landed in Papua New Guinea, the Solomon Islands and the Bismarck Archipelago. By May 1942 they had captured the Philippines. Malaya, Singapore, the Dutch East Indies, Burma and Siam were theirs. The Pacific island chain they had taken and quickly fortified was intended to form an arc of steel against any attempt by their enemies to retake their mainland prizes. Each island and archipelago would have to be individually recaptured by the Allies over the next three years.

The Battle of the Coral Sea, 28 April - 8 May 1942, was the first great battle between aircraft carrier fleets and the planes that were their main weapons. The Allied fleet prevented the Japanese from landing troops on the southern coast of Papua New Guinea within striking distance of Australia. Each fleet lost one carrier, so in naval terms this was an indecisive engagement. But the Battle of Midway the following month was a resounding defeat for the Japanese fleet, which lost all its carriers to US aircraft strikes. In August the Americans landed on Guadalcanal island in the Solomons; they did not retake it until the following February. By the end of 1942, after bitter jungle fighting in which Australian soldiers fought with tremendous bravery, the Japanese had been pushed back to the northern coast of Papua.

All through 1943 the Americans advanced through the Solomon Islands. The Japanese were driven out of Papua and confined to the northern part of New Guinea. Then the Americans began an island-by-island advance towards Japan. By February 1944 they had retaken the Gilbert and Marshall Islands north-east of the Solomons; by July the Carolines and the Marianas, halfway between Papua New Guinea and Japan.

In October 1944 the Americans landed on Leyte in the Philippines, and the Japanese fleet came to oppose them. In the ensuing Battle of Leyte Gulf - in spite of the introduction of kamikaze suicide pilot attacks against Allied ships - the Japanese fleet was heavily defeated, and in fact would never operate effectively again. Had the Americans known that, they might not have continued their costly island-by-island policy - one of the main points of which was to establish bases from which to operate against the Japanese navy. However, island-by-island it remained: the two infamous islands of Iwo Jima and Okinawa, next in line towards Japan. Both were heavily defended; both cost enormous numbers of lives - Iwo Jima 6,000 Americans and 21,000 Japanese, Okinawa 12,500 Americans and a staggering 110,000 Japanese.

Okinawa finally fell on 21 June 1945. By then the main Japanese cities lay in ruins from aerial bombardment; the Japanese navy and air force were virtually annihilated. The Allies issued a demand for an unconditional surrender on 26 July; the reply seemed equivocal. So on 6 August the Allies dropped an atomic bomb on Hiroshima; three days later, another on Nagasaki. Next day the Japanese accepted defeat, and on 2 September 1945 they signed articles of unconditional surrender.
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