World War II

War in the Pacific


The Beginning of the War in the Pacific

The seeming imminence of a Soviet defeat in the summer and fall of 1941 had created dilemmas for Japan and the U.S. The Japanese thought they then had the best opportunity to seize the petroleum and other resources of Southeast Asia and the adjacent islands; on the other hand, they knew they could not win the war with the U.S. that would probably ensue. The U.S. government wanted to stop Japanese expansion but doubted whether the American people would be willing to go to war to do so. Moreover, the U.S. did not want to get embroiled in a war with Japan while it faced the ghastly possibility of being alone in the world with a triumphant Germany. After the oil embargo, the Japanese, also under the pressure of time, resolved to move in Southeast Asia and the nearby islands.

Pearl Harbor

 Until December 1941 the Japanese leadership pursued two courses: They tried to get the oil embargo lifted on terms that would still let them take the territory they wanted, and they prepared for war. The U.S. demanded that Japan withdraw from China and Indochina, but would very likely have settled for a token withdrawal and a promise not to take more territory. After he became Japan's premier in mid-October, General Tojo Hideki set November 29 as the last day on which Japan would accept a settlement without war. Tojo's deadline, which was kept secret, meant that war was practically certain.

The Japanese army and navy had, in fact, devised a war plan in which they had great confidence. They proposed to make fast sweeps into Burma, Malaya, the East Indies, and the Philippines and, at the same time, set up a defensive perimeter in the central and southwest Pacific. They expected the United States to declare war but not to be willing to fight long or hard enough to win. Their greatest concern was the U.S. Pacific Fleet, based at Pearl Harbor, Hawaii. If it reacted quickly, it could scramble their very tight timetable. As insurance, the Japanese navy undertook to cripple the Pacific Fleet by a surprise air attack.

A few minutes before 8 AM on Sunday, December 7, 1941, Japanese carrier-based airplanes struck Pearl Harbor. In a raid lasting less than two hours, they sank four battleships and damaged four more. The U.S. authorities had broken the Japanese diplomatic code and knew an attack was imminent. A warning had been sent from Washington, but, owing to delays in transmission, it arrived after the raid had begun. In one stroke, the Japanese navy scored a brilliant success—and assured the Axis defeat in World War II. The Japanese attack brought the U.S. into the war on December 8—and brought it in determined to fight to the finish. Germany and Italy declared war on the United States on December 11.

Japanese Conquests in Asia and the Pacific

 In the vast area of land and ocean they had marked for conquest, the Japanese seemed to be everywhere at once. Before the end of December, they took British Hong Kong and the Gilbert Islands (now Kiribati) and Guam and Wake Island (U.S. possessions), and they had invaded British Burma, Malaya, Borneo, and the American-held Philippines. British Singapore, long regarded as one of the world's strongest fortresses, fell to them in February 1942, and in March they occupied the Netherlands East Indies and landed on New Guinea. The American and Philippine forces surrendered at Bataan on April 9, and resistance in the Philippines ended with the surrender of Corregidor on May 6.

According to the Japanese plan, it would be time for them to take a defensive stance when they had captured northern New Guinea (an Australian possession), the Bismarck Archipelago, the Gilberts, and Wake Island, which they did by mid-March. But they had done so well that they decided to expand their defensive perimeter north into the Aleutian Islands, east to Midway Island, and south through the Solomon Islands and southern New Guinea. Their first move was by sea, to take Port Moresby on the southeastern tip of New Guinea. The Americans, using their ability to read the Japanese code, had a naval task force on the scene. In the ensuing Battle of the Coral Sea (May 7-8), fought entirely by aircraft carriers, the Japanese were forced to abandon their designs on Port Moresby. See Coral Sea, Battle of the.

The Battle of Midway

A powerful Japanese force, nine battleships and four carriers under Admiral Yamamoto Isoroko, the commander in chief of the navy, steamed toward Midway in the first week of June. Admiral Chester W. Nimitz, who had taken command of the Pacific Fleet after Pearl Harbor, could only muster three carriers and seven heavy cruisers, but he was reading the Japanese radio messages. Yamamoto, the architect of the Pearl Harbor raid, had planned another surprise. This time, however, it was he who was surprised. Off Midway, on the morning of June 4, U.S. dive-bombers destroyed three of the Japanese carriers in one 5-minute strike. The fourth went down later in the day, after its planes had battered the U.S. carrier Yorktown, which sank two days later. See Midway, Battle of.

Yamamoto ordered a general retreat on June 5. On June 6-7 a secondary Japanese force took Kiska and Attu in the Aleutians, but those were no recompense for the defeat at Midway, from which the Japanese navy would never recover. Their battleships were intact, but the Coral Sea and Midway had shown carriers to be the true capital ships of the war, and four of those were gone.

The Third Phase: Turn of the Tide

 In late December 1941 Roosevelt and Churchill and their chief advisers met in Washington. They reaffirmed the strategy of defeating Germany first, and because it appeared that the British would have all they could do fighting in Europe, the war against Japan became almost solely a U.S. responsibility. They also created the Combined Chiefs of Staff (CCS), a top-level British-American military committee seated in Washington, to develop and execute a common strategy. On January 1, 1942, the United States, Great Britain, the USSR, and 23 other countries signed the United Nations Declaration in which they pledged not to make a separate peace. The United Nations became the official name for the anti-Axis coalition, but the term used more often was the Allies, taken over from World War I.

Development of Allied Strategy

As a practical matter, the U.S. could not take much action in Europe in early 1942. It had no troops there, and it was in the midst of building forces and converting industry at home. In North Africa, the British appeared to be more than holding their own. They had relieved Tobruk on December 10, 1941, and taken Banghazì in Libya two weeks later. Rommel counterattacked in late January 1942 and drove them back 300 km (185 mi) to al-Gazala and Bir Hacheim, but there, well forward of Tobruk and the Egyptian border, a lull set in.


The big question in the war was whether the USSR could survive a second German summer offensive, and the Russians were urging the U.S. and Britain to relieve the pressure on them by starting an offensive in the west. General George C. Marshall, the U.S. Army chief of staff, believed the best way to help the Russians and bring an early end to the war was to stage a buildup in England and attack across the English Channel into northwestern Europe. He wanted to act in the spring of 1943, or even in 1942 if the USSR appeared about to collapse. The British did not want involvement elsewhere until North Africa was settled and did not believe a force strong enough for a cross-channel attack could be assembled in England by 1943. Rommel settled the issue. In June he captured Tobruk and drove 380 km (235 mi) into Egypt, to Al ‘Alamayn (El ‘Alamein). After that, the Americans agreed to shelve the cross-channel attack and ready the troops en route to England for an invasion of French North Africa.

The Pacific

Meanwhile, despite the Germany-first strategy, the Americans were moving toward an active pursuit of the war against Japan. The U.S. Navy saw the Pacific as an arena in which it could perform more effectively than in the Atlantic or the Mediterranean. General Douglas MacArthur, who had commanded in the Philippines and been evacuated to Australia by submarine before the surrender, was the country's best-known military figure and as such too valuable to be left with an inconsequential mission. The Battle of Midway had stopped the Japanese in the central Pacific, but they continued to advance in the southwest Pacific along the Solomons chain and overland on New Guinea. On July 2, 1942, the U.S. Joint Chiefs of Staff (JCS) directed the naval and ground forces in the south and southwest Pacific to halt the Japanese, drive them out of the Solomons and northeastern New Guinea, and eliminate the great base the Japanese had established at Rabaul, on New Britain in the Bismarck Archipelago (now in Papua New Guinea).


 The Axis was riding a high tide in midsummer 1942. Stalingrad and the Caucasus oil were seemingly within Hitler's grasp, and Rommel was within striking distance of the Suez Canal. The Japanese had occupied Guadalcanal at the southern end of the Solomons chain and were marching on Port Moresby. Within the next six months, however, the Axis had been stopped and turned back in the Soviet Union, North Africa, and the southwest Pacific.

U.S. Marines landed on Guadalcanal on August 7, 1942. Against a small Japanese garrison, the landing was easy. Afterward nothing was easy. The Japanese responded swiftly and violently by sea and by air. The outcome hinged on the Japanese navy's ability to bring in reinforcements, which was substantial, and the U.S. Navy's ability to keep the marines supplied, which was at times in some doubt. While the marines battled a determined foe in a debilitating tropical climate, between August 24 and November 30 the navy fought six major engagements in the waters surrounding the island. The losses in ships and aircraft were heavy on both sides, but the Japanese were more seriously hurt because they could not afford to accept a war of attrition with the Americans. Their warships did not come out again after the end of November, and the Americans declared the island secure on February 9, 1943.

Allied Strategy Against Japan

Strategy in the war with Japan evolved by stages during 1943. In the first, the goal was to secure bases on the coast of China (from which Japan could be bombed and later invaded) by British and Chinese drives through Burma and eastern China and by American thrusts through the islands of the central and southwestern Pacific to Formosa (Taiwan) and China. By midyear, it was apparent that neither the British nor the Chinese drive was likely to materialize. Thereafter, only the two American thrusts remained. Their objectives were still Formosa and the Chinese coast.

U.S. Advances in the Pacific

In the Pacific, U.S. troops retook Attu, in the Aleutians, in a hard-fought, 3-week battle beginning on May 23. (The Japanese evacuated Kiska before Americans and Canadians landed there in August.) The main action was in the southwest Pacific. There U.S. and New Zealand troops, under Admiral William Halsey, advanced through the Solomons, taking New Georgia in August and a large beachhead on Bougainville in November. Australians and Americans under MacArthur drove the Japanese back along the East Coast of New Guinea and took Lae and Salamaua in September. MacArthur's and Halsey's mission, as set by the JCS in 1942, had been to take Rabaul, but they discovered in the Solomons that having command of the air and sea around them was enough to neutralize the Japanese Island garrisons and render them useless. Landings on Cape Gloucester, New Britain, in December, in the Admiralty Islands in February 1944, and At Emirau Island in March 1944 effectively sealed off Rabaul. Its 100,000-man garrison could not thereafter be either adequately supplied or evacuated.

The central Pacific thrust was slower in getting started. The southwest Pacific islands were relatively close together; airfields on one could furnish support for the move to the next; and the Japanese navy was wary of risking its ships within range of land-based aircraft. In the central Pacific, however, the islands were scattered over vast stretches of ocean, and powerful naval forces were needed to support the landings, particularly aircraft carriers, which were not available in sufficient numbers until late 1943.

The first central Pacific landings were in the Gilbert Islands, at Makin and Tarawa in November 1943. Betio Island in the Tarawa Atoll, 117.8 hectares (291 acres) of coral sand and concrete and coconut log bunkers, cost the 2nd Marine Division 3000 casualties in three days. More intensive preliminary bombardments and larger numbers of amphibian tractors capable of crossing the surrounding reefs made the taking of Kwajalein and Eniwetok in the Marshall Islands in February 1944 somewhat less expensive.

The Battle of the Philippine Sea

Operations against Japan in the Pacific picked up speed in 1944. In the spring, the JCS projected advances by MacArthur through northwestern New Guinea and into the Philippines and by Nimitz across the central Pacific to the Marianas and Caroline Islands. The Japanese, on their part, were getting ready for a decisive naval battle east of the Philippines.

After making leaps along the New Guinea coast to Aitape, Hollandia, and Wakde Island in April and May, MacArthur's troops landed on Biak Island on May 27. Airfields on Biak would enable U.S. planes to harass the Japanese fleet in the Philippines. A striking force built around the world's two largest battleships, Yamato and Musashi, was steaming toward Biak on June 13 when the U.S. Navy began bombing and shelling Saipan in the Marianas. The Japanese ships were then ordered to turn north and join the First Mobile Fleet of Admiral Ozawa Jisaburo, which was heading out of the Philippines toward the Marianas.

On June 19 and 20, Ozawa met U.S. Task Force 58, under Admiral Marc A. Mitscher, in the Battle of the Philippine Sea. The outcome was decided in the air and under the sea. Ozawa had five heavy and four light carriers; Mitscher had nine heavy and six light carriers. On the first day, in what was called the Marianas Turkey Shoot, U.S. fighters downed 219 of 326 Japanese planes sent against them. While the air battle was going on, U.S. submarines sank Ozawa's two largest carriers, one of them his flagship; and on the second day, dive-bombers sank a third big carrier. After that, Ozawa steered north toward Okinawa with just 35 planes left. It was the end for Japanese carrier aviation. Mitscher lost 26 planes, and 3 of his ships suffered minor damage.

 Strategic Shift in the Pacific

U.S. forces landed on Saipan on June 15. The Americans had possession of Saipan, Tinian, and Guam by August 10, giving them the key to a strategy for ending the war. The islands could accommodate bases for the new American long-range bombers, the B-29 Superfortresses, which could reach Tokyo and the other main Japanese cities at least as well from the islands as they would have been able to from bases in China. Moreover, U.S. naval superiority in the Pacific was rapidly becoming sufficient to sustain an invasion of Japan itself across the open ocean. That invasion, however, would have to wait for the defeat of Germany and the subsequent release of ground troops from Europe for use in the Pacific. The regular bombing of Japan began in November 1944.

Although the shift in strategy raised some doubts about the need for the operations in the Carolines and Philippines, they went ahead as planned, with landings in the western Carolines at Peleliu (September 15), Ulithi (September 23), and Ngulu (October 16) and in the central Philippines on Leyte (October 20). The invasion of the Philippines brought the Japanese navy out in force for the last time in the war. In the 3-day Battle for Leyte Gulf (October 23-25), the outcome of which was at times more in doubt than the final result would seem to indicate, the Japanese lost 26 ships, including the giant battleship Musashi, and the Americans lost 7 ships.

 The Defeat of Japan

 Although Japan's position was hopeless by early 1945, an early end to the war was not in sight. The Japanese navy would not be able to come out in force again, but the bulk of the army was intact and was deployed in the home islands and China. The Japanese gave a foretaste of what was yet in store by resorting to kamikaze (Japanese, "divine wind") attacks, or suicide air attacks, during the fighting for Luzon in the Philippines. On January 4-13, 1945, quickly trained kamikaze pilots flying obsolete planes had sunk 17 U.S. ships and damaged 50. See Kamikaze.

Iwo Jima and Okinawa

While the final assault on Japan awaited reinforcements from Europe, the island-hopping approach march continued, first, with a landing on Iwo Jima on February 19. That small, barren island cost the lives of over 6000 U.S. Marines before it was secured on March 16. Situated almost halfway between the Marianas and Tokyo, the island played an important part in the air war. Its two airfields provided landing sites for damaged B-29s and enabled fighters to give the bombers cover during their raids on Japanese cities.

On April 1 the U.S. Tenth Army, composed of four army and four marine divisions under General Simon B. Buckner, Jr., landed on Okinawa, 500 km (310 mi) south of the southernmost Japanese island, Kyushu. The Japanese did not defend the beaches. They proposed to make their stand on the southern tip of the island, across which they had constructed three strong lines. The northern three-fifths of the island were secured in less than two weeks, the third line in the south could not be breached until June 14, and the fighting continued to June 21.

Hiroshima and Nagasaki

 The next attack was scheduled for Kyushu in November 1945. An easy success seemed unlikely. The Japanese had fought practically to the last man on Iwo Jima, and hundreds of soldiers and civilians had jumped off cliffs at the southern end of Okinawa rather than surrender. Kamikaze planes had sunk 15 naval vessels and damaged 200 off Okinawa.

The Kyushu landing was never made. Throughout the war, the U.S. government and the British, believing Germany was doing the same, had maintained a massive scientific and industrial project to develop an atomic bomb. The chief ingredients, fissionable uranium and plutonium, had not been available in sufficient quantity before the war in Europe ended. The first bomb was exploded in a test at Alamogordo, New Mexico, on July 16, 1945.

Two more bombs had been built, and the possibility arose of using them to convince the Japanese to surrender. President Harry S. Truman decided to allow the bombs to be dropped because, he said, he believed they might save thousands of American lives. For maximum psychological impact, they were used in quick succession, one over Hiroshima on August 6, the other over Nagasaki on August 9. These cities had not previously been bombed, and thus the bombs' damage could be accurately assessed. U.S. estimates put the number killed in Hiroshima at 66,000 to 78,000 and in Nagasaki at 39,000. Japanese estimates gave a combined total of 240,000. The USSR declared war on Japan on August 8 and invaded Manchuria the next day.

The Japanese Surrender

 On August 14 Japan announced its surrender, which was not quite unconditional because the Allies had agreed to allow the country to keep its emperor. The formal signing took place on September 2 in Tokyo Bay aboard the battleship Missouri. The Allied delegation was headed by General MacArthur, who became the military governor of occupied Japan.