Pacific War

The Pacific War was the part of World War II—and preceding conflicts—that took place in the Pacific Ocean, its islands, and in East Asia, between July 7, 1937, and August 14, 1945. The most decisive actions took place after the Empire of Japan attacked various countries, who together came to be known as the Allies (or Allied powers), on or after December 7, 1941, including an attack on United States forces at Pearl Harbor.

Today, most Japanese also use the term "Pacific War" (太平洋戦争), while a few Japanese use the term "Greater East Asia War" (大東亜戦争), officially adopted by the Imperial General Headquarters in 1941 and banned in 1945, during the occupation of Japan.

Participants
The major Allied participants were the United States (including forces of the Philippines colony), China, and the United Kingdom (including the forces of British India), Australia, New Zealand. The Netherlands (as possessor of the Dutch East Indies), Canada, Mexico, Free French Forces and many other countries also took part, especially forces from other British colonies. The Soviet Union fought two short, undeclared border conflicts (Battle of Lake Khasan and Battle of Khalkhin Gol) with Japan in 1938 and 1939, then remained neutral until August 1945, when it joined the Allies and invaded Manchukuo in an operation known as Operation August Storm.

The Axis states which assisted Japan included the Japanese puppet states of Manchukuo and the Wang Jingwei Government (which controlled the coastal regions of China). Thailand joined the Axis powers under duress, and her army participated in the invasion and occupation of northeastern Burma. Japan enlisted many soldiers from its colonies of Korea and Formosa (now called Taiwan). German and Italian naval forces also operated in the Pacific and Indian Oceans, though this was to a comparatively small extent.

Theatres
Between 1942 and 1945, there were four main areas of conflict in the Pacific War, ie. the war against Japan: China, the Central Pacific, South East Asia and the South West Pacific.

U.S. sources refer to two theaters within the Pacific War: the Pacific Theater of Operations (PTO) and the China Burma India Theater (CBI). However these were not operational commands. In the PTO, the Allies divided operational control of their forces between two supreme commands, known as Pacific Ocean Areas and Southwest Pacific Area.

In 1945, for brief period just before the Japanese surrender, the Soviet Union and its Mongolian ally engaged Japanese forces in Manchuria and northeast China.

Background
The roots of the war began in the late 19th century with China in political chaos and Japan rapidly modernising. Over the course of the late 19th century and early 20th century, Japan intervened and finally annexed Korea and expanded its political and economic influence into China, particularly Manchuria. This expansion of power was aided because by the 1910s, China had fragmented into warlordism with only a weak and ineffective central government.

However, the situation of a weak China unable to resist Japanese demands appeared to be changing toward the end of the 1920s. In 1927, Generalissimo Chiang Kai-shek and the National Revolutionary Army of the Kuomintang (KMT) led the Northern Expedition. Chiang was able to defeat the warlords in southern and central China, and was in the process of securing the nominal allegiance of the warlords in northern China. Fearing that Zhang Xueliang, the warlord controlling Manchuria, was about to declare his allegiance to Chiang, the Japanese staged the Mukden Incident in 1931 and set up the puppet state of Manchukuo. The nominal Emperor of this puppet state was better known as Henry Pu Yi of the defunct Qing Dynasty.

Japan's imperialist goals in China were to maintain a secure supply of natural resources and to have puppet governments in China that would not act against Japanese interests. Although Japanese actions would not have seemed out of place among European colonial powers in the 19th century, by 1930, notions of Wilsonian self-determination meant that raw military force in support of colonialism was no longer seen as appropriate behavior by the international community.

Hence Japanese actions in Manchuria were roundly criticised and led to Japan's withdrawal from the League of Nations. During the 1930s, China and Japan reached a stalemate with Chiang focusing his efforts at eliminating the Communist Party of China, whom he considered to be a more fundamental danger than the Japanese. The influence of Chinese nationalism on opinion both in the political elite and the general population rendered this strategy increasingly untenable.

Though they had at first cooperated in the Northern Expedition, during the period of 1930–34, the nationalist KMT and the Chinese Communist Party entered into direct conflict. The Japanese capitalised on the infighting between Chinese factions to make greater inroads, forcing a landing at Shanghai in 1932.

Meanwhile, in Japan, a policy of assassination by secret societies and the effects of the Great Depression had caused the civilian government to lose control of the military. In addition, the military high command had limited control over the field armies who acted in their own interest, often in contradiction to the overall national interest. Pan-Asianism was also used as a justification for expansion. This is perhaps best summarized by the "Amo Doctrine" of 1934, issued by Eiji Amo, head of information department of the Japanese Foreign Ministry. Known as the "Monroe Doctrine of Asia," it announced Japan's intention for European countries to adopt a "hands off" policy in China, thereby negating the Open Door Policy. It stated that Japan was to be the sole leader in security in East Asia, including the task of defeating communism. Economic reason was also a very important factor leading to the invasion of China. During the Great Depression, Japanese exports to American and European markets were severely curtailed, and Japan turned to completely dominating China politically and economically to provide a stable market. In the period leading up to full-scale war in 1937, Japan's use of force in localised conflicts to threaten China unless the latter reduced its protective tariff and suppressed anti-Japanese activities and boycotts were evidence to this.

Second Sino-Japanese War
In 1936, Chiang was kidnapped by Zhang Xueliang. As a condition of his release, Chiang agreed to form a united front with the communists and fight the Japanese. Soon after, the Marco Polo Bridge Incident took place on July 7, 1937, which succeeded in provoking a war between the Republic of China and the Empire of Japan. Though the Nationalist and Communist Chinese would cooperate in military campaigns against Japan and sought to create a united national front, Mao Zedong refused to directly submit to the Kuomintang, and the aim of the Communists remained social revolution. In 1939, the Chinese Communist Red Army consisted of 500,000 troops independent of the KMT.

In 1939 Japanese forces tried to push into the Soviet Far East from Manchuria. They were soundly defeated in the Battle of Khalkhin Gol by a mixed Soviet and Mongolian force led by Georgy Zhukov. This stopped Japanese expansion to the north, and Japan and the Soviet Union kept an uneasy peace until 1945.

In addition, throughout the 1930s Japan succeeded in alienating public opinion in the West, particularly the United States and Britain. During the early 1930s, public opinion in the United States had been neutral. However, news reports of the Panay incident caused American public opinion to swing against Japan.

By 1941, the conflict had become a stalemate. Although Japan had occupied much of north and central China, the Kuomintang had retreated to the interior with a provisional capital set up at Chungking while the Chinese communists remained in control of base areas in Shaanxi. In addition, Japanese control of north and central China was somewhat tenuous, in that Japan was usually able to control railroads and the major cities ("points and lines"), but did not have a major military or administrative presence in the vast Chinese countryside. The Japanese found that its aggression against the retreating and regrouping Chinese army was stalled by the mountainous terrain in southwestern China while the Communists organised widespread guerrilla and saboteur activities in eastern and central China behind the Japanese front line.

Japan sponsored several puppet governments, one of which was headed by Wang Jingwei. However, its policies of brutality toward the Chinese population, of not yielding any real power to the governments, and of supporting several rival governments failed to make any of them a popular alternative to Chiang's government. Japan was also unwilling to negotiate directly with Chiang, nor was it willing to attempt to create splits in the Chinese united front.

War spreads in the East
In an effort to discourage Japan's war efforts in China, the United States, Britain, and the Dutch government in exile (still in control of the oil-rich Dutch East Indies) stopped selling oil and steel to Japan. It was known as the "ABCD encirclement" (American-British-Chinese-Dutch) designed to deny Japan of the raw materials needed to continue its war in China. Japan saw this as an act of aggression, and without these resources Japan's military machine would grind to a halt. On December 8, 1941, Japanese forces attacked the British crown colony of Hong Kong, the International Settlement in Shanghai, and the Philippines, which was then a United States Commonwealth. Japan also used Vichy French bases in French Indochina to invade Thailand, then using the gained Thai territory to launch an assault against Malaya.

In the belief the U.S. would inevitably come to Britain's aid, simultaneously (December 7 in the Western Hemisphere), Japan launched a carrier-based air attack on Pearl Harbor, hoping to avoid prolonged war and, when faced with this sudden and massive defeat, the United States would agree to a negotiated settlement and allow Japan free reign in China. Admiral Yamamoto stated I shall run wild considerably for the first six months or a year, but I have utterly no confidence for the second and third years. This calculated gamble did not pay off; the United States refused to negotiate. Furthermore, American losses were less serious than initially thought; the American carriers were at sea, while vital base facilities like the fuel oil storage tanks and Navy Yard, loss of which could have crippled the Pacific Fleet, were untouched. Moreover, the Submarine Base and intelligence unit ( HYPO ), which made the largest contributions to Japan's defeat, were also unaffected.

United States enters the war


Until the attack on Pearl Harbor, the United States had remained out of the Asian and European conflict. The America First Committee, 800,000 members strong, had until that day vehemently opposed any American intervention in the foreign conflict, even as America provided military aid to Britain and Soviet Union through the Lend-Lease program. Opposition to war in the United States vanished after the attack. Four days after Pearl Harbor, on December 11, Nazi Germany declared war on the United States, drawing America into a two-theater war. In 1941, Japan had only a fraction of the manufacturing capacity of the United States and was therefore perceived as a lesser threat than Germany.

British, Indian, and Dutch forces, already drained of personnel and matériel by two years of war with Germany, and heavily committed in the Middle East, North Africa and elsewhere, were unable to provide much more than token resistance to the battle-hardened Japanese. The Allies suffered many disastrous defeats in the first six months of the war. Two major British warships, HMS Repulse and HMS Prince of Wales were sunk by a Japanese air attack off Malaya on December 10, 1941. The government of Thailand surrendered within 24 hours of Japanese aggression and formally allied itself with Japan on December 21, allowing its military bases to be used as a launchpad against Singapore and Malaya. Hong Kong fell on December 25, and U.S. bases on Guam and Wake Island were lost at around the same time.

Following the January 1, 1942 Declaration by the United Nations (not to be confused with the United Nations Organization, organised after World War II), the Allied governments appointed the British General Sir Archibald Wavell as supreme commander of all "American-British-Dutch-Australian" (ABDA) forces in South East Asia. This gave Wavell nominal control of a huge but thinly-spread force covering an area from Burma to the Dutch East Indies and the Philippines. Other areas, including India, Australia and Hawaii remained under separate local commands. On January 15, Wavell moved to Bandung in Java to assume control of ABDA Command (ABDACOM).

Japanese offensives, 1941-42
In January, Japan invaded Burma, the Dutch East Indies, New Guinea, the Solomon Islands and they captured Manila, Kuala Lumpur and Rabaul. After being driven out of Malaya, Allied forces in Singapore attempted to resist the Japanese during the battle of Singapore but surrendered to the Japanese on February 15 1942; about 130,000 Indian, Australian and British troops along with Dutch sailors, became prisoners of war. The pace of conquest was rapid: Bali and Timor also fell in February. The rapid collapse of Allied resistance had left the "ABDA area" split in two. Wavell resigned from ABDACOM on February 25, handing control of the ABDA Area to local commanders and returning to the post of Commander-in-Chief, India.

At the battle of the Java Sea in late February and early March, the Japanese Navy inflicted a resounding defeat on the main ABDA naval force, under Admiral Karel Doorman. The Netherlands East Indies campaign subsequently ended with the surrender of Allied forces on Java.

The British, under intense pressure, made a fighting retreat from Rangoon to the Indo-Burmese border. This cut the Burma Road which was the western Allies' supply line to the Chinese Nationalists. Cooperation between the Chinese Nationalists and the Communists had waned from its zenith at the Battle of Wuhan, and the relationship between the two had gone sour as both attempted to expand their area of operations in occupied territories. Most of the Nationalist guerrilla areas were eventually overtaken by the Communists. On the other hand, some Nationalist units were deployed to blockade the Communists and not the Japanese. Furthermore, many of the forces of the Chinese Nationalists were warlords allied to Chiang Kai-Shek, but not directly under his command. "Of the 1,200,000 troops under Chiang's control, only 650,000 were directly controlled by his generals, and another 550,000 controlled by warlords who claimed loyalty to his government; the strongest force was the Szechuan army of 320,000 men. The defeat of this army would do much to end Chiang's power." The Japanese used these divisions to press ahead in their offenses.

Filipino and U.S. forces put up a fierce resistance in the Philippines until May 8 1942, when more than 80,000 of them surrendered. By this time, General Douglas MacArthur, who had been appointed Supreme Allied Commander South West Pacific, had relocated his headquarters to Australia. The U.S. Navy, under Admiral Chester Nimitz, had responsibility for the rest of the Pacific Ocean.

Meanwhile, Japanese aircraft had all but eliminated Allied air power in South-East Asia and were making attacks on northern Australia, beginning with a disproportionately large and psychologically devastating attack on the city of Darwin on February 19, which killed at least 243 people. A raid by a powerful Imperial Japanese Navy aircraft carrier force into the Indian Ocean resulted in the Battle of Ceylon and sinking of the only British carrier, HMS Hermes, in the theatre as well as 2 cruisers and other ships effectively driving the British fleet out of the Indian ocean and paving the way for Japanese conquest of Burma and a drive towards India. Air attacks on the U.S. mainland were insignificant, comprising of a submarine-based seaplane fire-bombing a forest in Oregon on September 9, 1942 (in 1944, fire balloon attacks were made using bombs carried to the United States from the Japanese mainland by the jetstream).

Allies re-group
In early 1942, the governments of smaller powers began to push for an inter-governmental Asia-Pacific war council, based in Washington D.C.. A council was established in London, with a subsidiary body in Washington. However the smaller powers continued to push for a U.S.-based body. The Pacific War Council was formed in Washington on April 1, 1942, with a membership consisting of President Franklin D. Roosevelt, his key advisor Harry Hopkins, and representatives from Britain, China, Australia, the Netherlands, New Zealand and Canada. Representatives from India and the Philippines were later added. The council never had any direct operational control, and any decisions it made were referred to the U.S.-British Combined Chiefs of Staff, which was also in Washington.

Allied resistance, at first symbolic, gradually began to stiffen. Australian and Dutch forces led civilians in a prolonged guerilla campaign in Portuguese Timor. The Doolittle Raid did minimal damage but was a huge morale booster for the Allies, especially the United States, and it caused repercussions throughout the Japanese military because they were sworn to protect the Japanese emperor and homeland but did not intercept, down, or damage a single bomber.

Coral Sea and Midway: the turning point


By mid-1942, the Japanese Combined Fleet found itself holding a vast area, even though it lacked the aircraft carriers, aircraft, and aircrew to defend it, and the freighters, tankers, and destroyers necessary to sustain it. Moreover, Fleet doctrine was incompetent to execute the proposed "barrier" defence. Instead, they decided on additional attacks in both the south and central Pacific. While Yamamoto had used the element of surprise at Pearl Harbor, Allied codebreakers now turned the tables. They discovered an attack against Port Moresby, New Guinea, was imminent with intent to invade and conquer all of New Guinea. If Port Moresby fell, it would give Japan control of the seas to the immediate north of Australia. Nimitz rushed the carrier USS Lexington, under Admiral Frank Fletcher, to join USS Yorktown and a U.S.-Australian task force, with orders to contest the Japanese advance. The resulting Battle of Coral Sea was the first naval battle in which ships involved never sighted each other and aircraft were solely used to attack opposing forces. Although Lexington was sunk and Yorktown seriously damaged, the Japanese lost the aircraft carrier Shōhō, suffered extensive damage to Shōkaku, took heavy losses to the air wing of Zuikaku (both missed the operation against Midway the following month), and saw the Moresby invasion force turn back. Even though losses were almost even, the Japanese attack on Port Moresby was thwarted and their invasion forces turned back, yielding a strategic victory for the Allies.

Destruction of U.S. carriers was Yamamoto's main objective, and he planned an operation to lure them to a decisive battle. After the Battle of Coral Sea, he had four frontline carriers operational &mdash; Sōryū, Kaga, Akagi and Hiryū &mdash; and believed Nimitz had a maximum of two: Enterprise and/or Hornet. Saratoga was out of action, undergoing repair after a torpedo attack, and Yorktown sailed after three days' work to repair her flight deck and make essential repairs, with civilian work crews still aboard.

Yamamoto planned to lure Nimitz's carriers into battle, splitting his fleet and thereby gaining a further advantage. A large Japanese force was sent north to attack and invade the Aleutian Islands, off Alaska. The next stage of Yamamoto's plan called for the capture of Midway Atoll, after which it would be turned into a major Japanese airbase. This would give Yamamoto control of the central Pacific and a much better opportunity to destroy Nimitz's remaining carriers. In May, however, Allied codebreakers discovered Midway was the true target. Nagumo was again in tactical command but was focused on the invasion of Midway; Yamamoto's complex plan had no provision for intervention by Nimitz before the Japanese expected him. Planned surveillance of the U.S. fleet by long range seaplane did not happen (as a result of an abortive identical operation in March), so U.S. carriers were able to proceed to a flanking position on the approaching Japanese fleet without being detected. Nagumo had 272 planes operating from his four carriers, the U.S. 348 (of which 115 were land-based).



As anticipated by U.S. commanders, the Japanese fleet arrived off Midway on June 4 and was spotted by PBY patrol aircraft. By the time the Japanese had launched planes against the island, U.S. planes had scrambled and were heading for Nagumo's carriers. However, initial U.S. attacks were poorly coordinated, piecemeal, and ineffectual; they failed to score a single hit, and half of them were lost. At 09:20 the first carrier aircraft arrived when Hornet's TBD Devastator torpedo bombers attacked; Zero fighters shot down all 15. At 09:35, 15 TBDs from Enterprise skimmed in over the water; 14 were shot down by Zeroes. The carrier aircraft had launched without coordinating their own dive bomber and fighter escort coverage so the torpedo bombers had arrived first, distracting Nagumo's Zeros. When the last of the U.S. Navy strike aircraft arrived, the Zeros could not protect their ships against a high-level dive bomber attack. In addition, his four carriers had drifted out of formation, reducing the concentration of their anti-aircraft fire. His most-criticized error was that although Nagumo ordered aircraft armed for shipping attack as a hedge against discovery of U.S. carriers, he changed arming orders twice, based on reports an additional strike was needed against Midway and the sighting of the American task force, wasting time and leaving his hangar decks crowded with refueling and rearming strike aircraft and ordnance stowed outside the magazines. Yamamoto's dispositions, which left Nagumo with inadequate reconnaissance to detect Fletcher before he launched, are often ignored.

When SBD Dauntless dive bombers from Enterprise and Yorktown appeared at an altitude of 10,000 feet, the Zeroes at sea level were unable to respond before the bombers tipped over in their dives. The U.S. bombers scored significant hits; Sōryū, Kaga, and Akagi all caught fire. Hiryū survived this wave of attacks and launched an attack against the American carriers which caused severe damage to Yorktown (which was later finished off by a Japanese submarine). A second attack from the U.S. carriers a few hours later found Hiryū and finished her off. Yamamoto had four reserve carriers with his separate surface forces, all too slow to keep up with the Kido Butai and therefore never in action. Yamamoto's enormous superiority in terms of naval artillery was irrelevant because the U.S. had air superiority at Midway and could refuse a surface gunfight (and, by remarkable good fortune, Spruance moved to avoid, based on a faulty submarine report ); Yamamoto's flawed dispositions had made closing to engage after dark on June 4 impossible. Midway was a decisive victory for the U.S. Navy and the high point in Japanese aspirations in the Pacific.

New Guinea and the Solomons
Japanese land forces continued to advance in the Solomon Islands and New Guinea. From July, 1942, a few Australian Militia (reserve) battalions, many of them very young and untrained, fought a stubborn rearguard action in New Guinea, against a Japanese advance along the Kokoda Track, towards Port Moresby, over the rugged Owen Stanley Ranges. The militia, worn out and severely depleted by casualties, were relieved in late August by regular troops from the Second Australian Imperial Force, returning from action in the Middle East.



In early September 1942, Japanese Special Naval Landing Forces (commonly, but erroneously, called "Japanese marines") attacked a strategic Royal Australian Air Force base at Milne Bay, near the eastern tip of New Guinea. They were beaten back by the Australian Army, inflicting the first outright defeat on Japanese land forces since 1939.

Guadalcanal
At the same time as major battles raged in New Guinea, Allied forces spotted a Japanese airfield under construction at Guadalcanal. The Allies made an amphibious landing in August to convert it to their use and start to reverse the tide of Japanese conquests. As a result, Japanese and Allied forces both occupied various parts of the island. Over the following six months, both sides fed resources into an escalating battle of attrition on the island, at sea, and in the sky, with eventual victory going to the Allies in February 1943. It was a campaign the Japanese could ill afford. A majority of Japanese aircraft from the entire South Pacific area was drained into the Japanese defence of Guadalcanal. The U.S. Air Forces based at Henderson Field became known as the Cactus Air Force (from the codename for the island), and held their own. The Japanese launched a pair of ill-coordinated attacks on U.S. positions around Henderson Field to suffer bloody repulse and then to suffer even worse losses to starvation and disease during the retreat. These offensives were suppiled by a series of ill-considered supply runs (called the "Tokyo Express" by the Americans), often also bringing about night battles with the U.S. Navy, expending destroyers IJN could not spare. Later fleet battles involving heavier ships and even daytime carrier battles resulted in near even losses to both sides, but only the American shipyards could quickly replace their losses. Japanese troops named Guadacanal "The Island of Death" as their fortunes declined. The Japanese survivors were evacuated in another series of "Tokyo Express" runs. The final American assaults found empty camps.

Allied advances in New Guinea and the Solomons
By late 1942, the Japanese were also retreating along the Kokoda Track in the highlands of New Guinea. Australian and U.S. counteroffensives culminated in the capture of the key Japanese beachhead in eastern New Guinea, the Buna-Gona area, in early 1943.

In June 1943, the Allies launched Operation Cartwheel, which defined their offensive strategy in the South Pacific. The operation was aimed at isolating the major Japanese forward base, at Rabaul, and cutting its supply and communication lines. This prepared the way for Nimitz's island-hopping campaign towards Japan.

Stalemate in China and South-East Asia
British Commonwealth forces were also counter-attacking in Burma, albeit with limited success.

In August 1943, the western Allies formed a new South East Asia Command (SEAC) to take over strategic responsibilities for Burma and India from the British India Command, under Wavell. In October 1943, Winston Churchill appointed Admiral Lord Louis Mountbatten as Supreme Allied Commander, SEAC. General William Slim was commander of Commonwealth land forces and directed the Burma Campaign. General Joseph Stilwell commanded U.S. forces in the CBI Theater, directed aid to China and assisted in the coordination of Chinese operations.

On November 22, 1943, U.S. President Franklin D. Roosevelt, British Prime Minister Winston Churchill, and ROC leader Chiang Kai-Shek met in Cairo, Egypt, to discuss a strategy to defeat Japan. The meeting was also known as Cairo Conference and concluded with the Cairo Declaration.

Allied offensives, 1943-44
Midway proved to be the last great naval battle for two years. The United States used the two years to turn its vast industrial potential into actual ships, planes, and trained aircrew. At the same time, Japan, lacking an adequate industrial base or technological strategy, a good aircrew training program, and adequate naval resources and doctrine for commerce defense, fell further and further behind. In strategic terms the Allies began a long movement across the Pacific, seizing one island base after another. Not every Japanese stronghold had to be captured; some, like Truk, Rabaul and Formosa were neutralized by air attack and bypassed. The goal was to get close to Japan herself, then launch massive strategic air attacks, improve the submarine blockade, and finally (only if necessary) execute an invasion.

In November 1943, U.S. Marines sustained high casualties when they overwhelmed the 4,500-strong garrison at Tarawa. This helped the Allies to improve the techniques of amphibious landings, learning from their mistakes and implementing changes such as thorough pre-emptive bombings and bombardment, more careful planning regarding tides and landing craft schedules, and better overall coordination.

The U.S. Navy did not seek out the Japanese fleet for a decisive battle, as Mahanian doctrine would suggest (and as Japan hoped); the Allied advance could only be stopped by a Japanese naval attack, which oil shortages (induced by submarine attack) made impossible.

Submarine warfare
U.S. submarines (with some aid from the British and Dutch), operating from bases in Australia, Hawaii, and Ceylon, played a major role in defeating Japan. This was the case even though submarines made up a small proportion of the Allied navies—less than two percent in the case of the U.S. Navy. Submarines strangled Japan by sinking its merchant fleet, intercepting many troop transports, and cutting off nearly all the oil imports essential to weapons production and military operations. By early 1945 the oil tanks were dry. Japan thought its defensive techniques sank 468 American subs; the true figure was only 42. (Ten others went down in accidents, the Atlantic Ocean, or as the result of friendly fire.) Submarines also rescued hundreds of downed fliers.

U.S. submarines accounted for 56% of the Japanese merchantmen sunk; most of the rest were hit by planes at the end of the war, or were destroyed by mines. U.S. submariners also claimed 28% of Japanese warships destroyed. Furthermore, they played important reconnaissance roles, as at the battles of the Philippine Sea and Leyte Gulf (and, coincidentally, at Midway), when they gave accurate and timely warning of the approach of the Japanese fleet. Submarines operated from secure bases in Fremantle, Australia; Pearl Harbor; Trincomalee, Ceylon; and later Guam. These bases were protected by surface fleets and aircraft.

Submarines did not adopt a defensive posture and wait for the enemy to attack. Within hours of Pearl Harbor, Roosevelt ordered a new doctrine into effect: unrestricted submarine warfare against Japan. This meant sinking any warship, commercial vessel, or passenger ship in Axis controlled waters, without warning and without help to survivors.



While Japan had a large number of submarines, they did not make a significant impact on the war. In 1942, the Japanese fleet subs performed well, knocking out or damaging many Allied warships. However, Imperial Japanese Navy (and prewar U.S.) doctrine stipulated naval campaigns are won only by fleet battles, not guerre de course (commerce raiding). So, while the U.S. had an unusually long supply line between its west coast and frontline areas, and was vulnerable to submarine attack, Japan's submarines were instead primarily used for long range reconnaissance and only occasionally attacked U.S. supply lines. The Japanese submarine offensive against Australia in 1942 and 1943 also achieved little. As the war turned against Japan, IJN submarines were increasingly used to resupply strongholds which had been cut off, such as Truk and Rabaul. In addition, Japan honored its neutrality treaty with the Soviet Union and ignored U.S. freighters shipping millions of tons of war supplies from San Francisco to Vladivostok.

The U.S. Navy, by contrast, relied on commerce raiding from the outset. However, the problems of MacArthur's forces trapped in the Philippines led to diversion of boats to "guerrilla submarine" missions. As well, basing in Australia placed boats under Japanese aerial threat while en route to patrol areas, inhibiting effectiveness, and Nimitz relied on submarines for close surveillance of enemy bases. Furthermore, the standard issue Mark XIV torpedo and its Mark VI exploder were both defective, problems not corrected until September 1943. Worst of all, before the war, an uninformed Customs officer had seized a copy of the Japanese merchant marine code (called the "maru code" in the USN), not knowing Office of Naval Intelligence (ONI) had broken it; Japan promptly changed it, and it was not recovered until 1943.

Thus it was not until 1944 that the U.S. Navy began to use its 150 submarines to maximum effect: effective shipboard radar was installed, commanders lacking in aggression were replaced, and faults in torpedoes were fixed. Japanese commerce protection was "shiftless beyond description," and convoys were poorly organised and defended compared to Allied ones, a product of flawed IJN doctrine and training&mdash;errors concealed by American faults as much as Japanese overconfidence. The number of U.S. submarines on patrol at any one time increased from 13 in 1942, to 18 in 1943, to 43 in late 1944. Half of their kills came in 1944, when over 200 subs were operating. By 1945, patrols had decreased because so few targets dared to move on the high seas. In all, Allied submarines destroyed 1,200 merchant ships. Most were small cargo carriers, but 124 were tankers bringing desperately needed oil from the East Indies. Another 320 were passenger ships and troop transports. At critical stages of the Guadalcanal, Saipan, and Leyte campaigns, thousands of Japanese troops were killed before they could be landed. Over 200 warships were sunk, ranging from many auxiliaries and destroyers to eight carriers and one battleship. Underwater warfare was especially dangerous; of the 16,000 Americans who went out on patrol, 3,500 (22%) never returned, the highest casualty rate of any American force in World War II. The Japanese losses were even higher.

A single German submarine, U-862, operated in the Pacific Ocean during the war, patrolling off the Australian east coast and New Zealand in December 1944 and January 1945. It sank one ship in the Pacific before it was recalled to Batavia.

Japanese counteroffensives in China, 1944
In mid-1944, Japan launched a massive invasion across China, under the code name Operation Ichigo. These attacks, the biggest in several years, gained much ground for Japan before they were stopped in Guangxi.

Saipan and Philippine Sea:
On June 15, 1944, 535 ships began landing 128,000 U.S. Army and Marine personnel on the island of Saipan. The Allied objective was the creation of airfields &mdash; within B-29 range of Tokyo. The ability to plan and execute such a complex operation in the space of 90 days was indicative of Allied logistical superiority.

It was imperative for Japanese commanders to hold Saipan. The only way to do this was to destroy the U.S. 5th Fleet, which had 15 big carriers and 956 planes, 28 battleships and cruisers, and 69 destroyers. Vice Admiral Jisaburo Ozawa attacked with nine-tenths of Japan's fighting fleet, which included nine carriers with 473 planes, 18 battleships and cruisers, and 28 destroyers. Ozawa's pilots were outnumbered 2-1 and their aircraft were becoming obsolete. The Japanese had substantial AA guns but lacked proximity fuzes and good radar. With the odds stacked against him, Ozawa devised an appropriate strategy. His planes had greater range because they were not weighed down with protective armor; they could attack at about 480 km (300 mi), and could search a radius of 900 km (560 mi). U.S. Navy Hellcat fighters could only attack within 200 miles and only search within a 325 mile radius. Ozawa planned to use this advantage by positioning his fleet 300 miles out. The Japanese planes would hit the U.S. carriers, land at Guam to refuel, then hit the enemy again, when returning to their carriers. Ozawa also counted on about 500 ground-based planes at Guam and other islands.



Admiral Raymond A. Spruance was in overall command of the 5th Fleet. The Japanese plan would have failed if the much larger U.S. fleet had closed on Ozawa and attacked aggressively; Ozawa had the correct insight that the unaggressive Spruance would not attack. U.S. Admiral Marc Mitscher, in tactical command of Task Force 58, with its 15 carriers, was aggressive but Spruance vetoed Mitscher's plan to hunt down Ozawa because Spruance's personal doctrine made it his first priority to protect the soldiers landing on Saipan.

The forces converged in the largest sea battle of World War II up to that point. Over the previous month American destroyers had destroyed 17 of the 25 submarines Ozawa had sent ahead. Repeated U.S. raids destroyed the Japanese land-based planes. Ozawa's main attack lacked coordination, with the Japanese planes arriving at their targets in a staggered sequence. Following a directive from Nimitz, the U.S. carriers all had combat information centers, which interpreted the flow of radar data instantaneously and radioed interception orders to the Hellcats. The result was later dubbed the Great Marianas Turkey Shoot. The few attackers to reach the U.S. fleet encountered massive AA fire with proximity fuzes. Only one American warship was slightly damaged.

On the second day U.S. reconnaissance planes finally located Ozawa's fleet, 275 miles away and submarines sank two Japanese carriers. Mitscher launched 230 torpedo planes and dive bombers. He then discovered that the enemy was actually another 60 miles further off, out of aircraft range. Mitscher decided that this chance to destroy the Japanese fleet was worth the risk of aircraft losses. Overall, the U.S. lost 130 planes and 76 aircrew. However, Japan lost 450 planes, three carriers and 445 pilots. The Imperial Japanese Navy's carrier force was effectively destroyed.

Leyte Gulf 1944
The Battle of Leyte Gulf was arguably the largest naval battle in history. It was a series of four distinct engagements fought off the Philippine island of Leyte from October 23 to October 26 1944. Leyte Gulf featured the largest battleships ever built, it was the last time in history that battleships engaged each other, and was also notable as the first time that kamikaze aircraft were used. Allied victory in the Philippine Sea established Allied air and sea superiority in the western Pacific. Nimitz favored blockading the Philippines and landing on Formosa. This would give the Allies control of the sea routes to Japan from southern Asia, cutting off substantial Japanese garrisons. MacArthur favoured an invasion of the Philippines, which also lay across the supply lines to Japan. Roosevelt adjudicated in favor of the Philippines. Meanwhile, Japanese Combined Fleet Chief Toyoda Soemu prepared four plans to cover all Allied offensive scenarios. On October 12, Nimitz launched a carrier raid against Formosa to make sure that planes based there could not intervene in the landings on Leyte. Soemu put Plan Sho-2 into effect, launching a series of air attacks against the U.S. carriers. However the Japanese lost 600 planes in three days, leaving them without air cover.

Sho-1 called for V. Adm. Jisaburo Ozawa's force to use an apparently vulnerable carrier force to lure the U.S. 3rd Fleet away from Leyte and remove air cover from the Allied landing forces, which would then be attacked from the west by three Japanese forces: V. Adm. Takeo Kurita's force would enter Leyte Gulf and attack the landing forces; R. Adm. Shoji Nishimura's force and V. Adm. Kiyohide Shima's force would act as mobile strike forces. The plan was likely to result in the destruction of one or more of the Japanese forces, but Toyoda justified it by saying that there would be no sense in saving the fleet and losing the Philippines.

Kurita's "Center Force" consisted of five battleships, 12 cruisers and 13 destroyers. It included the two largest battleships ever built: Yamato and Musashi. As they passed Palawan Island after midnight on October 23, the force was spotted, and U.S. submarines sank two cruisers. On October 24, as Kurita's force entered the Sibuyan Sea, USS Intrepid and USS Cabot  launched 260 planes, which scored hits on several ships. A second wave of planes scored many direct hits on Musashi. A third wave, from USS Enterprise and USS Franklin hit Musashi with 11 bombs and eight torpedoes. Kurita retreated but in the evening turned around to head for San Bernardino Strait. Musashi sank at about 19:30.

Meanwhile, V. Adm. Onishi Takijiro had directed his First Air Fleet, 80 land-based planes, against U.S. carriers, whose planes were attacking airfields on Luzon. USS Princeton was hit by an armour-piercing bomb and suffered a major explosion which killed 200 crew and 80 on a cruiser which was alongside. Princeton sank, and the cruiser was forced to retire.

Nishimura's force consisted of two battleships, one cruiser and four destroyers. Because they were observing radio silence, Nishimura was unable to synchronise with Shima and Kurita. Nishimura and Shima had failed to even coordinate their plans before the attacks - they were long time rivals and neither wished to have anything to do with the other. When he entered the narrow Surigao Strait at about 02:00, Shima was 22 miles (40 km) behind him, and Kurita was still in the Sibuyan Sea, several hours from the beaches at Leyte. As they passed Panaon Island, Nishimura's force ran into a trap set for them by the U.S.-Australian 7th Fleet Support Force. R. Adm. Jesse Oldendorf had six battleships, four heavy cruisers, four light cruisers, 29 destroyers and 39 PT boats. To pass the strait and reach the landings, Nishimura had to run the gauntlet. At about 03:00 the Japanese battleship Fuso and three destroyers were hit by torpedoes and Fuso broke in two. At 03:50 the U.S. battleships opened fire. Radar fire control meant they could hit targets from a much greater distance than the Japanese. The battleship Yamashiro, a cruiser and a destroyer were crippled by 16-inch (406mm) shells; Yamashiro sank at 04:19. Only one of Nishimura's force of seven ships survived the engagement. At 04:25 Shima's force of two cruisers and eight destroyers reached the battle. Seeing Fuso and believing her to be the wrecks of two battleships, Shima ordered a retreat.

Ozawa's "Northern Force" had four aircraft carriers, two obsolete battleships partly converted to carriers, three cruisers and nine destroyers. The carriers had only 108 planes. The force was not spotted by the Allies until 16:40 on October 24. At 20:00 Soemu ordered all remaining Japanese forces to attack. Halsey saw an opportunity to destroy the remnants of the Japanese carrier force. The U.S. Third Fleet was formidable &mdash; nine large carriers, eight light carriers, six battleships, 17 cruisers, 63 destroyers and 1,000 planes &mdash; and completely outgunned Ozawa's force. Halsey's ships set out in pursuit of Ozawa just after midnight. U.S. commanders ignored reports that Kurita had turned back towards San Bernardino Strait. They had taken the bait set by Ozawa. On the morning of October 25, Ozawa launched 75 planes. Most were shot down by U.S. fighter patrols. By 08:00 U.S. fighters had destroyed the screen of Japanese fighters and were hitting ships. By evening, they had sunk the carriers Zuikaku, Zuiho, and Chiyoda, and a destroyer. The fourth carrier, Chitose and a cruiser were disabled and later sank.

Kurita passed through San Bernardino Strait at 03:00 on 25 October and headed along the coast of Samar. The only thing standing in his path was three groups (Taffy 1, 2 and 3) of the Seventh Fleet, commanded by Admiral Thomas Kinkaid. Each group had six escort carriers, with a total of more than 500 planes, and seven or eight destroyers or destroyer escorts (DE). Kinkaid still believed that Lee's force was guarding the north, so the Japanese had the element of surprise when they attacked Taffy 3 at 06:45. Kurita mistook the Taffy carriers for large fleet carriers and thought he had the whole Third Fleet in his sights. Since escort carriers stood little chance against a battleship, Adm. Clifton Sprague directed the carriers of Taffy 3 to turn and flee eastward, hoping that bad visibility would reduce the accuracy of Japanese gunfire, and used his destroyers in to divert the Japanese battleships. The destroyers made harassing torpedo attacks against the Japanese. For ten minutes Yamato was caught up in evasive action. Two U.S. destroyers and a DE were sunk, but they had bought enough time for the Taffy groups to launch planes. Taffy 3 turned and fled south, with shells scoring hits on some of its carriers and sinking one of them. The superior speed of the Japanese force allowed it to draw closer and fire on the other two Taffy groups. However, at 09:20 Kurita suddenly turned and retreated north. Signals had disabused him of the notion that he was attacking the Third Fleet, and the longer Kurita continued to engage, the greater the risk of major air strikes. Destroyer attacks had broken the Japanese formations, shattering tactical control, and two of Kurita's heavy cruisers had been sunk. The Japanese retreated through the San Bernardino Strait, under continuous air attack. The Battle of Leyte Gulf was over.

The battle secured the beachheads of the U.S. Sixth Army on Leyte against attack from the sea, broke the back of Japanese naval power and opened the way for an advance to the Ryukyu Islands in 1945. The only significant Japanese naval operation afterwards was the disastrous Operation Ten-Go, in April 1945. Kurita's force had begun the battle with five battleships; when he returned to Japan, only Yamato was combat-worthy. Nishimura's sunken Yamashiro was the last battleship to engage another in combat.

Philippines, 1944-45


On October 20 1944, the U.S. Sixth Army, supported by naval and air bombardment, landed on the favorable eastern shore of Leyte, one of the three large Philippine Islands, north of Mindanao. The U.S. Sixth Army continued its advance from the east, as the Japanese rushed reinforcements to the Ormoc Bay area on the western side of the island. While the Sixth Army was reinforced successfully, the U.S. Fifth Air Force was able to devastate the Japanese attempts to resupply. In torrential rains and over difficult terrain, the advance continued across Leyte and the neighboring island of Samar to the north. On December 7, U.S. Army units landed at Ormoc Bay and, after a major land and air battle, cut off the Japanese ability to reinforce and supply Leyte. Although fierce fighting continued on Leyte for months, the U.S. Army was in control.

On December 15 1944, landings against minimal resistance were made on the southern beaches of the island of Mindoro, a key location in the planned Lingayen Gulf operations, in support of major landings scheduled on Luzon. On January 9 1945, on the south shore of Lingayen Gulf on the western coast of Luzon, General Krueger's Sixth Army landed his first units. Almost 175,000 men followed across the twenty-mile beachhead within a few days. With heavy air support, Army units pushed inland, taking Clark Field, 40 miles northwest of Manila, in the last week of January.

Two more major landings followed, one to cut off the Bataan Peninsula, and another, that included a parachute drop, south of Manila. Pincers closed on the city and, on February 3 1945, elements of the 1st Cavalry Division pushed into the northern outskirts of Manila and the 8th Cavalry passed through the northern suburbs and into the city itself.

As the advance on Manila continued from the north and the south, the Bataan Peninsula was rapidly secured. On February 16, paratroopers and amphibious units assaulted Corregidor, and resistance ended there on February 27.

In all, ten U.S. divisions and five independent regiments battled on Luzon, making it the largest campaign of the Pacific war, involving more troops than the United States had used in North Africa, Italy, or southern France.

Palawan Island, between Borneo and Mindoro, the fifth largest and western-most Philippine Island, was invaded on February 28, with landings of the Eighth Army at Puerto Princesa. The Japanese put up little direct defence of Palawan, but cleaning up pockets of Japanese resistance lasted until late April, as the Japanese used their common tactic of withdrawing into the mountain jungles, disbursed as small units. Throughout the Philippines, U.S. forces were aided by Filipino guerrillas to find and dispatch the holdouts.

The U.S. Eighth Army then moved on to its first landing on Mindanao (17 April), the last of the major Philippine Islands to be taken. Mindanao was followed by invasion and occupation of Panay, Cebu, Negros and several islands in the Sulu Archipelago. These islands provided bases for the U.S. Fifth and Thirteenth Air Forces to attack targets throughout the Philippines and the South China Sea.

Allied offensives in Burma, 1944-45
The British launched a series of offensive operations back into Burma during late 1944 and the first half of 1945. Command of the British formations on the front was rearranged in November 1944; the 11th Army Group was replaced with Allied Land Forces South East Asia.

The Japanese Burma Area Army withdrew the 15th Army behind the Irrawaddy River (Operation BAN). 28th Army was to continue to defend the Arakan and lower Irrawaddy valley (Operation KAN), while 33rd Army would attempt to prevent the completion of the new Ledo Road between India and China by defending Bhamo and Lashio, and mounting guerrilla raids (Operation DAN).

In Arakan, as the monsoon ended, the British Commonwealth XV Corps resumed its advance on Akyab Island for the third year in succession. This time the Japanese were numerically far weaker, and had already lost the most favorable defensive positions. The Indian 25th Infantry Division advanced on Foul Point and Rathedaung at the end of the Mayu Peninsula, while the West African 81st Division and West African 82nd Division converged on Myohaung at the mouth of the Kaladan River. The Japanese evacuated Akyab Island on December 31, 1944. It was occupied by XV Corps without resistance two days later.

Following the incursion into western Burma, XV Corps operations were halted in order to transfer transport aircraft to support Fourteenth Army. With the coastal area secured the Allies were free to build sea-supplied airbases on the two offshore islands, Ramree Island and Cheduba. Cheduba, the smaller of the two islands, had no Japanese garrison, but the clearing of the small but typically tenacious Japanese garrison on Ramree took about six weeks

NCAC's operations were limited from late 1944 onwards by the need for Chinese troops on the main front in China. The American and British commanders attacked the Chinese leadership's decision to focus their limited resources on the defensive of Chinese cities rather than the defeat of the Japanese in Burma. In spite of these limitations, General Sultan was still able to resume his advance against the Japanese 33rd Army.

On his right, the British 36th Infantry Division, brought in to replace the Chindits, made contact with the Indian 19th Infantry Division near Indaw on December 10, 1944, and Fourteenth Army and NCAC now had a continuous front. Meanwhile, three Chinese divisions and a US Force known as the "Mars Brigade" (which had replaced Merrill's Marauders) advanced slowly from Myitkyina to Bhamo. The Japanese resisted for several weeks, but Bhamo fell on December 15.

Sultan's forces made contact with Chiang's Yunnan armies on January 21, 1945, and the Ledo road could finally be completed, although it was not yet secure. The Ledo road by this point in the war was also of uncertain value. It would not be completed soon enough to change the overall military situation in China. Chiang, to the annoyance of the British and Americans, ordered Sultan to halt his advance at Lashio, which was captured on March 7. In April, OSS Detachment 101 took over control of American forces from the NCAC, which had withdrawn to China, while the 36th Division withdrew to India.

Fourteenth Army made the main thrust into central Burma. It had IV Corps and XXXIII Corps under its command, with six infantry divisions, two armoured brigades and three independent infantry brigades. Logistics were the primary problem the advance faced. A carefully designed system involving large amounts of supply by air was introduced as well endless construction projects designed to improve the land route from India into Burma.



When it was realised that the Japanese had fallen back behind the Irrawaddy River, the plan was modified. Initially both corps had been attacking into the Shwebo Plain between the Chindwin and Irrawaddy rivers. Now, only XXXIII Corps would continue this attack, while IV Corps changed its axis of advance to the Gangaw Valley west of the Chindwin, aiming to cross the Irrawaddy close to Pakokku and then capture the main Japanese line of communication centre of Meiktila. Diversionary measures (such as dummy radio traffic) would persuade the Japanese that both corps were aimed at Mandalay.

The plan was completely successful. Allied air superiority and the thin Japanese presence on the ground meant that the Japanese were unaware of the strength of the force moving on Pakokku. During January and February, XXXIII Corps seized crossings over the Irrawaddy River near Mandalay. There was heavy fighting, which attracted Japanese reserves and fixed their attention. Late in February, Indian 7th Division, leading IV Corps, seized crossings at Nyaungu, near Pakokku. Indian 17th Division and 255th Indian Armoured brigade followed them across and struck for Meiktila.

While the Japanese were distracted by events at Meiktila, XXXIII Corps had renewed its attack on Mandalay. It fell to Indian 19th Division on March 20, though the Japanese held the former citadel of Fort Dufferin for another week. The battle was extremely costly in that much of the historically and culturally significant portions of Mandalay, including the old royal palace, were burned to the ground. With the fall of Mandalay (and of Maymyo to its east), communications to the Japanese front in the north of Burma were cut. The Japanese 15th Army was completely scattered, leaving only small detachments and parties of stragglers making their way east.

The Allied armies continued their southward drive towards Rangoon, with the goal of capturing the vital port before the monsoon season cut the overland supply routes. IV Corps made the main attack, down the "Railway Valley" by striking at the delaying position held by the remnants of Japanese 33rd Army at Pyawbwe. The Indian 17th Division and 255th Armoured Brigade were initially halted by a strong defensive position behind a dry chaung, but a flanking move by tanks and mechanized infantry struck the Japanese from the rear and shattered them. Following the route of the 33rd Army, organised resistance along the route to Rangoon all but ceased.

A general uprising delayed the Japanese 15th Division long enough for the Allied forces to reach the city of Toungoo, only 136 miles (219&nbs;km) from Rangoon. The Indian 17th Division reached Pegu, 40 miles (65 km) north of Rangoon by April 25. Kimura had formed the various service troops, naval personnel and even Japanese civilians in Rangoon into the Japanese 105 Independent Mixed Brigade. This scratch formation used buried aircraft bombs, anti-aircraft guns and suicide attacks with pole charges to delay the British advance, holding the British off until April 30, and covered the evacuation of the Rangoon area.

General Slim feared that the Japanese would defend Rangoon to the last man through the monsoon, which would put Fouteenth Army in a disastrous supply situation. His lines of communication by land were impossibly long, and the troops relied on supplies ferried by aircraft to airfields close behind the leading troops. Heavy rain would make these airfields unusable, and curtail flying. However, Kimura had ordered Rangoon to be evacuated, starting on April 22. Many troops were evacuated by sea, although British submarines claimed several ships. Kimura's own HQ left by land. The Japanese 105 Independent Mixed Brigade, by holding Pegu, covered this evacuation.

On May 1, a Gurkha parachute battalion was dropped on Elephant Point, which cleared Japanese rearguards from the mouth of the Rangoon River. The Indian 26th Infantry Division landed the next day and took over Rangoon, which had seen an orgy of looting and lawlessness similar to the last days of the British in the city in 1942. Following the capture of Rangoon, there were still Japanese forces to take care of in Burma, but it was largely a mopping up operation.

Liberation of Borneo


The Borneo Campaign of 1945 was the last major Allied campaign in the South West Pacific Area. In a series of amphibious assaults between May 1 and July 21, the Australian I Corps, under General Leslie Morshead, attacked Japanese forces occupying the island. Allied naval and air forces, centred on the U.S. 7th Fleet under Admiral Thomas Kinkaid, the Australian First Tactical Air Force and the U.S. Thirteenth Air Force also played important roles in the campaign.

The campaign opened with a landing on the small island of Tarakan on May 1. This was followed on June 1 by simultaneous assaults in the north west, on the island of Labuan and the coast of Brunei. A week later the Australians attacked Japanese positions in North Borneo. The attention of the Allies then switched back to the central east coast, with the last major amphibious assault of World War II, at Balikpapan on July 1.

Although the campaign was criticised in Australia at the time, and in subsequent years, as pointless or a "waste" of the lives of soldiers, it did achieve a number of objectives, such as increasing the isolation of significant Japanese forces occupying the main part of the Dutch East Indies, capturing major oil supplies and freeing Allied prisoners of war, who were being held in deteriorating conditions.

Landings in the Japanese home islands


Hard-fought battles on the Japanese home islands of Iwo Jima, Okinawa, and others resulted in horrific casualties on both sides but finally produced a Japanese retreat. Faced with the loss of most of their experienced pilots, the Japanese increased their use of kamikaze tactics in an attempt to create unacceptably high casualties for the Allies. The U.S. Navy proposed to force a Japanese surrender through a total naval blockade and air raids.

Towards the end of the war as the role of strategic bombing became more important, a new command for the U.S. Strategic Air Forces in the Pacific was created to oversee all U.S. strategic bombing in the hemisphere, under United States Army Air Forces General Curtis LeMay. Japanese industrial production plunged as nearly half of the built-up areas of 64 cities were destroyed by B-29 firebombing raids. On March 9-March 10, 1945 alone, about 100,000 people were killed in a fire storm caused by an attack on Tokyo. In addition, LeMay also oversaw Operation Starvation, in which the inland waterways of Japan were extensively mined by air, which disrupted the small amount of remaining Japanese coastal sea traffic.

Atomic bomb and the Soviet invasion
In August 1945, the U.S. dropped two nuclear weapons on the cities of Hiroshima and Nagasaki. More than 200,000 people died as a direct result of these two bombings. The necessity of these bombings has long been debated, with proponents arguing that the bombings obviated an invasion of the Home Islands.



On February 3 1945, the Soviet Union agreed with Roosevelt to enter the Pacific conflict. It promised to act 90 days after the war ended in Europe and did so exactly on schedule on August 9, by launching Operation August Storm. A battle-hardened, one million-strong Soviet force, transferred from Europe attacked Japanese forces in Manchuria and quickly defeated their Kwantung Army.

In Japan, August 14 is considered to be the day that the Pacific War ended. However, Imperial Japan actually surrendered on August 15, and this day became known in the English-speaking countries as "V-J Day" (Victory in Japan). The formal Instrument of Surrender was signed on September 2, 1945, on the battleship USS Missouri in Tokyo Bay. The surrender was accepted by General Douglas MacArthur as Supreme Allied Commander, with representatives of each Allied nation, from a Japanese delegation led by Mamoru Shigemitsu and Yoshijiro Umezu.

A separate surrender ceremony between Japan and China was held in Nanking on September 9, 1945.

Following this period, MacArthur went to Tokyo to oversee the postwar development of the country. This period in Japanese history is known as the occupation.

Timeline
Second Sino-Japanese war
 * 7 July 1937 – 9 September 1945

Japanese conquest of Southeast Asia and Pacific

 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-07 (12-08 Asian Time) Attack on Pearl Harbor
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-08 Japanese Invasion of Thailand
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-08 Battle of Guam (1941)
 * 1941-12-08 United States declares war on Japan
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-08 – 1941-12-25 Battle of Hong Kong
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-08 – 1942-01-31 Battle of Malaya
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-10 Sinking of HMS Prince of Wales and HMS Repulse
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-11 – 1941-12-24 Battle of Wake Island
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-16 – 1942-04-01 Borneo campaign (1942)
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1941-12-22 – 1942-05-06 Battle of the Philippines
 * 1942-01-01 – 1945-10-25 Transport of POWs via Hell Ships
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-01-11 – 1942-01-12 Battle of Tarakan
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-01-23 Battle of Rabaul (1942)
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-01-24 Naval Battle of Balikpapan
 * 1942-01-25 Thailand declares war on the Allies
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-01-30 – 1942-02-03 Battle of Ambon
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-01-30 – 1942-02-15 Battle of Singapore
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-02-04 Battle of Makassar Strait
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-02-14 – 1942-02-15 Battle of Palembang
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-02-19 Air raids on Darwin, Australia
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-02-19 – 1942-02-20 Battle of Badung Strait
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-02-19 – 1943-02-10 Battle of Timor (1942-43)
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-02-27 – 1942-03-01 Battle of the Java Sea
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-03-01 Battle of Sunda Strait
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-03-01 – 1942-03-09 Battle of Java
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-03-31 Battle of Christmas Island
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-03-31 – 1942-04-10 Indian Ocean raid
 * 1942-04-09 Bataan Death March begins
 * [[Image:Flag of USA.svg|20px|]] 1942-04-18 Doolittle Raid
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-05-03 Japanese invasion of Tulagi
 * [[Image:Flag of USA.svg|20px|]] 1942-05-04 – 1942-05-08 Battle of the Coral Sea
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-05-31 – 1942-06-08 Attacks on Sydney Harbour area, Australia
 * [[Image:Flag of USA.svg|20px|]] 1942-06-04 – 1942-06-06 Battle of Midway

Pacific War campaigns
Burma Campaign: 1941-12-16 – 1945-08-15

New Guinea campaign
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-01-23 – Battle of Rabaul
 * 1942-03-07 – Operation Mo (Japanese invasion of mainland New Guinea)
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1942-05-04 – 1942-05-08 Battle of the Coral Sea
 * [[Image:Flag of Australia.svg|20px|]] 1942-07-01 – 1943-01-31 Kokoda Track Campaign
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1942-08-25 – 1942-09-05 Battle of Milne Bay
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1942-11-19 – 1942-01-23 Battle of Buna-Gona
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1943-01-28 – 1943-01-30 Battle of Wau
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1943-03-02 – 1943-03-04 Battle of the Bismarck Sea
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1943-06-29 – 1943-09-16 Battle of Lae
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of New Zealand.svg|20px]] [[Image:US flag 48 stars.svg|20px]] 1943-06-30 – 1944-03-25 Operation Cartwheel
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1943-09-19 – 1944-04-24 Finisterre Range campaign
 * [[Image:Flag of Australia.svg|20px]] [[Image:US flag 48 stars.svg|20px]] 1943-09-22 – 1944-01-15 Huon Peninsula campaign
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of New Zealand.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1943-11-01 – 1943-11-11 Attack on Rabaul
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of New Zealand.svg|20px]] [[Image:US flag 48 stars.svg|20px]] 1943-12-15 – 1945-08-15 New Britain campaign
 * [[Image:US flag 48 stars.svg|20px]] 1944-02-29 – 1944-03-25 Admiralty Islands campaign
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1944-04-22 – 1945-08-15 Western New Guinea campaign

Aleutian Islands campaign
 * [[Image:Canadian Red Ensign.svg|20px]] [[Image:US flag 48 stars.svg|20px]] 1942-06-06 – 1943-08-15 Battle of the Aleutian Islands
 * [[Image:Canadian Red Ensign.svg|20px]] [[Image:US flag 48 stars.svg|20px]] 1942-06-07 – 1943-08-15 Battle of Kiska
 * [[Image:US flag 48 stars.svg|20px]] 1943-03-26 – Battle of the Komandorski Islands

Guadalcanal campaign
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of New Zealand.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] [[Image:Flag of Tonga.svg|20px|]] 1942-08-07 – 1943-02-09 Battle of Guadalcanal
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-08-09 Battle of Savo Island
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1942-08-24 – 1942-08-25 Battle of the Eastern Solomons
 * [[Image:US flag 48 stars.svg|20px]] 1942-10-11 – 1942-10-12 Battle of Cape Esperance
 * 1942-10-25 – 1942-10-27 Battle of the Santa Cruz Islands
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1942-11-13 – 1942-11-15 Naval Battle of Guadalcanal
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1942-11-30 Battle of Tassafaronga

Solomon Islands campaign
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1943-01-29 – 1943-01-30 Battle of Rennell Island
 * [[Image:US flag 48 stars.svg|20px]] 1943-03-06 Battle of Blackett Strait
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of New Zealand.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] [[Image:Flag of Fiji.svg|20px]] 1943-06-10 – 1943-08-25 Battle of New Georgia
 * 1943-07-06 Battle of Kula Gulf
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1943-07-12 – 1943-07-13 Battle of Kolombangara
 * [[Image:US flag 48 stars.svg|20px]] 1943-08-06 – 1943-08-07 Battle of Vella Gulf
 * [[Image:Flag of Japan (bordered).svg|20px|]] 1943-08-17 – 1943-08-18 Battle off Horaniu
 * [[Image:Flag of New Zealand.svg|20px]] [[Image:US flag 48 stars.svg|20px]] [[Image:Flag of Fiji.svg|20px]] 1943-08-15 – 1943-10-09 Land Battle of Vella Lavella
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of New Zealand.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] [[Image:Flag of Fiji.svg|20px]] 1943-11-01 – 1945-08-21 Battle of Bougainville
 * [[Image:US flag 48 stars.svg|20px]] 1943-11-01 – 1943-11-02 Battle of Empress Augusta Bay
 * [[Image:US flag 48 stars.svg|20px]] 1943-11-26 Battle of Cape St. George

Gilbert and Marshall Islands campaign
 * [[Image:US flag 48 stars.svg|20px]] 1943-11-20 – 1943-11-23 Battle of Tarawa
 * [[Image:US flag 48 stars.svg|20px]] 1943-11-20 – 1943-11-24 Battle of Makin
 * [[Image:US flag 48 stars.svg|20px]] 1944-01-31 – 1944-02-07 Battle of Kwajalein
 * [[Image:US flag 48 stars.svg|20px]] 1944-02-16 – 1944-02-17 Attack on Truk
 * [[Image:US flag 48 stars.svg|20px]] 1944-02-16 – 1944-02-23 Battle of Eniwetok

Mariana and Palau Islands campaign
 * [[Image:US flag 48 stars.svg|20px]] 1944-06-15 – 1944-07-09 Battle of Saipan
 * [[Image:US flag 48 stars.svg|20px]] 1944-06-19 – 1944-06-20 Battle of the Philippine Sea
 * [[Image:US flag 48 stars.svg|20px]] 1944-07-21 – 1944-08-10 Battle of Guam
 * [[Image:US flag 48 stars.svg|20px]] 1944-07-24 – 1944-08-01 Battle of Tinian
 * [[Image:US flag 48 stars.svg|20px]] 1944-09-15 – 1944-11-25 Battle of Peleliu
 * [[Image:US flag 48 stars.svg|20px]] 1944-09-17 – 1944-09-30 Battle of Angaur

Philippines campaign
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of the Philippines.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1944-10-20 – 1944-12-10 Battle of Leyte
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1944-10-24 – 1944-10-25 Battle of Leyte Gulf
 * [[Image:US flag 48 stars.svg|20px]] 1944-11-11 – 1944-12-21 Battle of Ormoc Bay
 * [[Image:US flag 48 stars.svg|20px]] 1944-12-15 – 1945-07-04 Battle of Luzon
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px]] 1945-01-09 Invasion of Lingayen Gulf
 * [[Image:US flag 48 stars.svg|20px]] 1945-02-27 – 1945-07-04 Southern Philippines campaign

Ryukyu Islands campaign
 * [[Image:flag of the United Kingdom.svg|20px]] 1945-01-24 – 1945-01-29 Operation Meridian
 * [[Image:US flag 48 stars.svg|20px]] 1945-02-16 – 1945-03-26 Battle of Iwo Jima
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Canadian Red Ensign.svg|20px]] [[Image:Flag of New Zealand.svg|20px]] [[Image:flag of the United Kingdom.svg|20px]] [[Image:US flag 48 stars.svg|20px]] 1945-04-01 – 1945-06-21 Battle of Okinawa
 * [[Image:US flag 48 stars.svg|20px]] 1945-04-07 Operation Ten-Go

Borneo campaign
 * [[Image:Flag of Australia.svg|20px|]] [[Image:Flag of the Netherlands.svg|20px]] [[Image:US flag 48 stars.svg|20px]] 1945-05-01 – 1945-05-25 Battle of Tarakan
 * [[Image:flag of the United Kingdom.svg|20px]] 1945-05-15 – 1945-05-16 Battle of the Malacca Strait
 * [[Image:Flag of Australia.svg|20px|]] 1945-06-10 – 1945-06-15 Battle of Brunei
 * [[Image:Flag of Australia.svg|20px|]] 1945-06-10 – 1945-06-22 Battle of Labuan
 * [[Image:Flag of Australia.svg|20px|]] 1945-06-17 – 1945-08-15 Battle of North Borneo
 * [[Image:Flag of Australia.svg|20px|]] [[Image:US flag 48 stars.svg|20px|]] 1945-07-07 – 1945-07-21 Battle of Balikpapan

Japan campaign
 * [[Image:US flag 48 stars.svg|20px|]] 1945-07-22 Battle of Tokyo Bay
 * [[Image:US flag 48 stars.svg|20px|]] 1945-08-06 – 1945-08-09 Atomic bombings of Hiroshima and Nagasaki