Japan: history 1941-45

The Japanese surrender at the end of World War II is accepted by Gen Douglas MacArthur on 2 September 1945, on board USS Missouri. This surrender announced the end of all fighting in World War II, and the beginning of the US occupation of Japan which continued until 1951.

For the history of Japan leading up to World War II, see Japan: history 1869-1912 and Japan: history 1912-41. For further details of the war in the east Asian and Pacific theatres, see World War II.

The Japanese attack on the US naval base at Pearl Harbor on 7 December 1941, and simultaneous attacks on other US and British bases in east Asia and the Pacific, was promptly followed by declarations of war against Japan by the USA and Britain. In the struggle that followed the Japanese were to fight with skill and courage, but also with extreme brutality; atrocities were perpetrated on a massive scale against combatants and noncombatants alike.

Early Japanese conquests Soon after the attack on Pearl Harbor, Japanese planes sank the British warships Prince of Wales and Repulse, thus consolidating the Japanese command of the seas in the south Pacific. By the early days of 1942 they had swept through Siam (Thailand) to Burma (Myanmar) and captured Penang, Hong Kong, and the greater part of the British Malay Peninsula, and were landing fresh troops in the Philippines (then a US territory).

Attempts by the Allies to hold fortresses and conduct campaigns without air cover failed disastrously: Hong Kong, Malaya, and Singapore were lost in this way; and the Japanese conquered the Dutch East Indies, Borneo, the Philippines, the Andamans, and most of Burma, and by cutting the Burma Road they isolated China. The eastward expansion of the Japanese was stopped by the Battle of the Coral Sea in May 1942, followed in June by the Battle of Midway. Their westward advance was stopped by the defeat of air attacks on Ceylon (Sri Lanka). Throughout 1942, however, the Japanese war took second place in the eyes of British and US statesmen, who were bent on intensifying their effort against Germany, which they regarded as by far the greater danger.

By pursuing an offensive in Papua the Japanese forces directly threatened the mainland of Australia, and it became essential for the Allies to check any further advance. Hence, in a strenuous campaign over jungle and mountain terrain, Australian troops repelled the invaders and captured Gona and Buna, the Japanese bases on the north coast of New Guinea, exterminating their garrisons.

The ‘island-hopping’ campaign While this war was in progress, US marines were landed on the large island of Guadalcanal in the Solomon Islands and by February 1943 had captured the island (see Guadalcanal, Battle of). This provided the launching pad for a long-drawn but effective process of ‘island hopping’, which gradually pierced the far-flung outer chain of strongholds covering Japan from the Pacific, a process in which the growing air and naval superiority of the USA eventually asserted itself.

For some time after the Japanese had been driven out of Guadalcanal no big land action was fought in the Pacific theatre, but the Americans continued to bomb Japanese bases, and by combined sea and air operations thwarted all Japanese efforts to reinforce their positions, especially in the Battle of the Bismarck Sea (March 1943) when Japan lost eight transports, four destroyers, and over 3,000 troops. In the middle of 1943 the Americans landed forces on New Georgia, while the Australians made progress along the north coast of New Guinea. Lae and Salamaua, the two chief Japanese bases on New Guinea, were taken by the Australians in September 1943. At the end of the year Rabaul, the great Japanese base in New Britain, was overcome by US forces, who were enabled to gain control through the construction of distant airfields.

The first territory taken from Japan, which was not a mere recovery but had been in Japanese hands before the war, was the Marshall Islands, which gave a base for bombing Truk, in the Caroline Islands, the greatest of Japan's Pacific bases. Continuing their westward and northward advance US forces, by the middle of 1944, reached the Mariana Islands and captured the strongly fortified island of Saipan, where at last they secured an air base within long-distance bombing range of both the Philippines and Japan itself.

Japan becomes vulnerable Political developments within Japan reflected the deterioration in the military and naval fields in 1944-45. Most serious of all, the Japanese navy was now definitely deprived of command of the sea even in those inner waters in which it was expected to have a great strategic advantage, so that Japan's shipping routes through the east and south China Seas, and even the coasts of Japan itself, were laid open to attack.

This meant the breakdown of Japan's original strategy, which relied on the bases in the Carolines, Marianas, Philippines, and Ryukyu Islands as ‘unsinkable aircraft carriers’ for covering Japan's maritime communications to the mainland of Asia and the Malay Archipelago, and for preventing a close approach of the enemy by sea to the Japanese homeland. It meant also that Japan was subjected more heavily to air attacks than was expected; the relative invulnerability given to Japan by its geographical remoteness from Allied bases was rapidly diminishing.

The war in Burma Japan's hope of using Burma as a springboard for invading India had been finally destroyed by the failure of the Japanese thrust into Manipur in the spring of 1944. But Burma was still useful for defending the land approaches to Siam and Malaya and blocking the Burma Road supply route to China. Hence Japan was prepared to fight stubbornly to hold it, and Japanese resistance was helped by the low priority for shipping and landing craft allotted to the Allied Southeast Asia Command under Lord Mountbatten. But by 1945 the Allied transport problem was overcome, largely by the use of airborne supplies, and with the capture of Mandalay the Japanese hold on Upper Burma was broken. Again, the Allied success at Myitkyina had led to the extension of the road from Ledo to meet the old Burma Road, and it was possible once more to send lorries through to China.

The Philippines campaign In striking contrast to the ship-starved offensive of the Southeast Asia Command of Mountbatten, the US invasion of the Philippines under US commander Gen Douglas MacArthur was carried out with an immense concentration of maritime transport and newly built landing craft. For Japan, therefore, everything depended on victory over the US fleet; without command of the sea the dispersed Japanese land forces would be isolated in their various captured islands.

It was the moment for Japan to risk a naval battle, and in October 1944 the main strength of the Japanese navy was deployed in a determined attempt to crush the US naval force that was covering the invasion of the island of Leyte in the Philippines.

It was now that the Japanese began to employ kamikaze tactics, with pilots plunging their own planes at US warships. But although they gained some dramatic successes, the Battle of Leyte Gulf was a decisive defeat for the Japanese and it decided the fate of the Philippines.

Japan on the defensive Strategically the US reconquest of Manila with the naval harbour of Cavite meant that all Japanese shipping routes south of Formosa (Taiwan) and Hong Kong were now exposed to close naval and air attack. The vast territories to the west and south of the South China Sea overrun by the Japanese since 1940, comprising Indochina, Siam, Burma, Malaya, and the Dutch East Indies, were now virtually cut off from Japan by sea. To all intents and purposes Japan had now lost the resources of its southern conquests, and its garrisons remaining there were almost as effectively isolated as the by-passed forces still holding out in New Guinea, New Britain, Bougainville, and Truk.

The Japanese hold on China, despite some continued successes there, was now threatened from a new direction - from the sea that the Japanese navy had formerly controlled, but controlled no longer. The Japanese, now that Germany was virtually beaten, had to prepare to defend Hong Kong, Guangzhou, Xiamen, and Shanghai against Allied seaborne invasion. They had also to prepare to defend Indochina against attack from the sea now that US forces were established in the Philippines.

The war comes to Japan For the ordinary Japanese, however, and indeed for their rulers, no theatre of war could compare with the homeland in importance. For the shinkoku or ‘divine land’ was now threatened with invasion from the sea. The loss of Saipan had brought down the cabinet of Gen Hideki Tōjō, and the fears aroused by this event were soon realized in raids by US long-range B-29 bombers on the industrial cities of central Japan, including Tokyo itself; firebomb raids on Tokyo in March 1945 killed at least 100,000 people.

Soon the new premier Gen Kuniaki Koiso had to admit the loss of the southern Japanese island of Iwo Jima (21 March 1945), despite a fanatical defence. The Japanese navy, after its mauling in the Philippine waters, had been in no shape to go to the rescue of the garrison. Then Admiral Nimitz invaded Okinawa, an island of the Ryukyu group commanding the sea approaches to Shanghai as well as to southwest Japan. The US air raids reached a climax in March-June, and with the promise of still worse to come.

Political intrigue and counter-intrigue went on between those who wished to try to negotiate some kind of peace settlement, once Germany was out of the war, and those who wanted to fight on to the bitter end. The Japanese garrison of 100,000 men on Okinawa, and other civilians, defended the island with the utmost tenacity, as indeed had the garrison of 20,000 on Iwo Jima, but organized resistance on Okinawa ceased on 21 June. The campaign in the Philippines ceased at the end of the month. On 14 July Japan was bombarded by US warships. On 26 July the Allied Powers issued the Potsdam Proclamation, threatening Japan with prompt and utter destruction unless it surrendered unconditionally. The new cabinet of Baron Kantaro Suzuki made no positive response, and on 6 August the first atomic bomb was dropped on Japan at Hiroshima; the second (and last) was dropped on Nagasaki on 9 August.

On the verge of surrender, Japan now found itself confronted by a new and powerful enemy in the USSR, which now declared war on Japan in order to wipe out the humiliation of past defeats and to restore the status quo of nearly half a century before. On 9 August the Red Army invaded Manchuria. Meanwhile Allied aircraft, operating from speedily organized runways on Okinawa, destroyed 60 Japanese ships in one day. This was the end. Though Japan still had a powerful fighter air force it was to a great extent a grounded force.

The Japanese surrender The measure of Japanese losses was catastrophic - some 3 million dead in total. For example, in New Guinea, of an army of originally 120,000 men only 12,000 survived. Between the date of the attack on Pearl Harbor and August 1945 some 300 Japanese warships had been sunk or put out of action, including 11 battleships, 16 heavy and 16 light cruisers, 23 aircraft carriers including 15 wartime conversions, 137 destroyers, 127 submarines, and a large number of minor war vessels. Japan's mercantile marine had practically disappeared. On land, sea, and in the air Japan was shattered and was now in fact faced with the prospect of speedy annihilation from further atomic bombs.

On 14 August Japan accepted the Allied demand for unconditional surrender. The Soviet declaration of war was a decisive factor: if the USSR had invaded successfully the imperial system would have been abolished, and if it had had a share in the occupation a permanent division of Japanese home territory would have been almost certain. Hence the decision to surrender to the Allies quickly, to avoid either of these threats. US forces began landing in Japan on 29 August and the instrument of unconditional surrender of Japan was signed on board the US battleship Missouri in Tokyo Bay on 2 September. Within the ensuing days of the month the Japanese forces in Luzon (in the Philippines) and throughout the southwest Pacific also surrendered, while the surrender in southeast Asia was received by Mountbatten on 2 September. That of the Japanese forces in China was signed in Nanjing by Gen Okamura on 9 September.

For Japanese history from 1945 to the present, see Japan.