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World War II - Asiatic-Pacific Theater Campaigns

World War II - Asiatic-Pacific Theater streamer

Streamers: Orange with two white, red, and white stripe groupings; with blue, white, and red stripes in the center.
Philippine Islands 7 December 1941 - 10 May 1942
Burma, 1942 7 December 1941 - 26 May 1942
Central Pacific 7 December 1941 - 6 December 1943
East Indies 1 January - 22 July 1942
India-Burma 2 April 1942 - 28 January 1945
Air Offensive, Japan 17 April 1942 - 2 September 1945
Aleutian Islands 3 June 1942 - 24 August 1943
China Defensive 4 July 1942 - 4 May 1945
Papua 23 July 1942 - 23 January 1943
Guadalcanal 7 August 1942 - 21 February 1943
New Guinea 24 January 1943 - 31 December 1944
Northern Solomons 22 February 1943 - 21 November 1944
Eastern Mandates 31 January - 14 June 1944
Bismarck Archipelago 15 December 1943 - 27 November 1944
Western Pacific 15 June 1944 - 2 September 1945
Leyte 17 October 1944 - 1 July 1945
Luzon 15 December 1944 - 4 July 1945
Central Burma 29 January - 15 July 1945
Southern Philippines 27 February - 4 July 1945
Ryukyus 26 March - 2 July 1945
China Offensive 5 May - 2 September 1945
 

The sections dealing with the Asiatic-Pacific and European-African-Middle Eastern Theaters of World War II were addressed differently than the other conflicts within this document. Many of the World War II campaigns extended over long periods of time, and overlapped other campaigns in the same theater. Consequently, the war in the Asiatic-Pacific Theater and that in the European-African-Middle Eastern Theater were treated as separate wars. Each war was described in a narrative style within a framework of broadly outlined operations. Within each operation there may have been more than one campaign covered. For example, the operation entitled Italy encompasses the Naples-Foggia, Anzio, Rome-Arno, North Apennines, and Po Valley campaigns.

Japanese military leaders recognized American naval strength as the chief deterrent to war with the United States. Early in 1941, Admiral Isoroku Yamamoto, Commander of the Japanese Combined Fleet, had initiated planning for a surprise attack on the United States Pacific Fleet at the beginning of any hostilities that the Japanese might undertake. The assumption was that before the United States could recover from a surprise blow, the Japanese would be able to seize all their objectives in the Far East, and could then hold out indefinitely. By September 1941 the Japanese had practically completed secret plans for a huge assault against Malaya, the Philippines, and the Netherlands East Indies, to be coordinated with a crushing blow on the Pacific Fleet at Pearl Harbor in the Hawaiian Island of Oahu. Early in November Vice Admiral Chuichi Nagumo was named commander of the Pearl Harbor Striking Force, which rendezvoused secretly in the Kuriles. The force of some 30 ships included 6 aircraft carriers with about 430 planes, of which approximately 360 took part in the subsequent attack. At the same time, a Japanese Advance Expeditionary Force of some 20 submarines was assembled at Kure naval base on the west coast of Honshu to cooperate in the attack.

Submarines of the Advance Expeditionary Force began their eastward movement across the Pacific in mid-November, refueled and resupplied in the Marshalls, and arrived near Oahu about 5 December (Hawaiian time). On the night of 6-7 December five midget (two-man) submarines that had been carried "piggy-back" on large submarines cast off and began converging on Pearl Harbor. Nagumo's task force sailed from the Kuriles on 26 November and arrived, undetected by the Americans, at a point about 200 miles north of Oahu at 0600 hours (Hawaiian time) on 7 December 1941. Beginning at 0600 and ending at 0715, a total of some 360 planes were launched in three waves. These planes rendezvoused to the south and then flew toward Oahu for coordinated attacks.

In Pearl Harbor were 96 vessels, the bulk of the United States Pacific Fleet. Eight battleships of the Fleet were there, but the aircraft carriers were all at sea. The Commander in Chief of the Pacific Fleet (CINCPAC) was Admiral Husband E. Kimmel. Army forces in Hawaii, including the 24th and 25th Infantry Divisions, were under the command of Lt. Gen. Walter C. Short, Commanding General of the Hawaiian Department. On the several airfields were a total of about 390 Navy and Army planes of all types, of which less than 300 were available for combat or observation purposes.

The Japanese air attack on Pearl Harbor and on the airfields of Oahu began at 0755 on 7 December 1941 and ended shortly before 1000. Quickly recovering from the initial shock of surprise, the Americans fought back vigorously with antiaircraft fire. Devastation of the airfields was so quick and thorough that only a few American planes were able to participate in the counterattack. The Japanese were successful in accomplishing their principal mission, which was to cripple the Pacific Fleet. They sunk three battleships, caused another to capsize, and severely damanged the other four. All together the Japanese sank or severely damaged 18 ships, including the 8 battleships, 3 light cruisers, and 3 destroyers. On the airfields the Japanese destroyed 161 American planes (Army 74, Navy 87) and seriously damaged 102 (Army 71, Navy 31). The Navy and Marine Corps suffered a total of 2,896 casualties of which 2,117 were deaths (Navy 2,008, Marines 109) and 779 wounded (Navy 710, Marines 69). The Army (as of midnight, 10 December) lost 228 killed or died of wounds, 113 seriously wounded and 346 slightly wounded. In addition, at least 57 civilians were killed and nearly as many seriously injured. The Japanese lost 29 planes over Oahu, one large submarine (on 10 December), and all 5 of the midget submarines. Their personnel losses (according to Japanese sources) were 55 airmen, 9 crewmen on the midget submarines, and an unknown number on the large submarines. The Japanese carrier task force sailed away undetected and unscathed.

On 8 December 1941, within less than an hour after a stirring, six-minute address by President Franklin D. Roosevelt, Congress voted, with only one member dissenting, that a state of war existed between the United States and Japan, and empowered the President to wage war with all the resources of the country.

Four days after Pearl Harbor, 11 December 1941, Germany and Italy declared war on the United States. Congress, this time without a dissenting vote, immediately recognized the existence of a state of war with Germany and Italy, and also rescinded an article of the Selective Service Act prohibiting the use of American armed forces beyond the Western Hemisphere.

Fall of the Philippines. The Philippine Department had been the outlying U.S. Army command in the Pacific for many years. In the summer of 1941 increasing tension between Japan and the United States caused the War Department to set up a new command for the specific purpose of organizing the defense of the Philippines. This command, activated on 26 July 1941, was named the United States Armed Forces, Far East (USAFFE, or AFFE); General Douglas MacArthur, retired, was placed on active duty and designated commanding general.

At the time of Pearl Harbor, General MacArthur's ground forces consisted of the Philippine Army of 10 divisions and supporting troops, with a total strength of about 100,000, and a U.S. Regular Army contingent of more than 25,000. Of the latter force, the largest unit was the Philippine Division, consisting of one American regiment and two Philippine Scout regiments. The Japanese struck before the Philippine Army could be completely trained or properly equipped.

The Japanese air attack on the Philippines on 8 December 1941 seriously crippled elements of the American air forces stationed in the islands and damaged naval installations. On 10 December Japanese forces landed at Aparri and Vigan on the northern coast of Luzon. The main body of the invasion force began landing on Luzon at Lingayen Gulf on 22 December. Other landings were made below Manila and on other islands of the Philippines. Unable to stop the enemy at the shoreline of Luzon, MacArthur withdrew sea forces into the Bataan Peninsula, the island of Corregidor, and three other small islands in Manila Bay. This complex retrograde movement was accomplished by 7 January 1942. Meanwhile, on 2 January, the Japanese had occupied Manila, which had been declared on open city on 24 December. The American and Filipino troops had lost most of their supplies during their withdrawal; and a Japanese blockade precluded the possibility of resupply or the landing of reinforcements.

On 12 March 1942, General MacArthur was ordered by the President to leave for Australia. His successor in command was Lt. Gen. Jonathan M. Wainwright who, for a short period (21 March to 6 May 1942), commanded the so-called U.S. Forces in the Philippines (USFIP), although General MacArthur remained the nominal commander.

On 9 April 1942, by which time the troops of Bataan had been reduced by hunger, disease, and casualties to the point of military helplessness, their commander, Maj. Gen. Edward P. King, Jr., surrendered his forces to the Japanese. General Wainwright surrendered the remainder of the American forces on Corregidor and elsewhere in the Philippines on 6 May 1942.

Asia and the Pacific. In the first seven months after Pearl Harbor the Japanese, at a surprisingly low cost, had gained control over a huge area extending from Burma to the Gilbert Islands and from the Aleutians to the Solomons. While the Japanese enjoyed the advantage of interior lines of communication, they had somewhat overextended themselves. Once the Allies became strong enough to threaten their perimeter from several directions, the advantage would be lost, since Japan did not have and could not produce enough planes and ships to defend in force at all points. In view of this danger, the Japanese prepared plans for an attack against the still weak Allied line of communications from the continental United States and Hawaii to Australia and for further expansion in the South Pacific. In May 1942 they launched a new offensive, moving to Tulagi from the northern Solomons, after which they began building an airstrip at Lunga Point on Guadalcanal. From there they hoped to disrupt the Allied line to Australia by seizing New Caledonia, the Fijis, and Samoa. At the same time, to give added protection to Rabaul, they moved into western New Britain and northeastern New Guinea. (Orders for invasions of New Caledonia, the Fijis, and Samoa were cancelled on 11 July 1942)

The Japanese suffered their first major setback when they attempted an invasion by sea of Port Moresby on the southeastern coast of New Guinea. Allied naval units intercepted the invading Japanese naval force in the Coral Sea on 7-8 May 1942. This was a clash between carrier task forces in which the surface ships did not exchange a shot. Most serious of the losses were the U.S. carrier Lexington and the Japanese carrier Shoho, while both sides suffered heavy losses in planes. After two days of fighting, the Japanese task force broke off the engagement and withdrew northward.

In the Coral Sea the U.S. Navy checked the Japanese; in the Battle of Midway, 3-6 June 1942, it defeated them, and the battle marked an important turning point in the war in the Pacific. Two American task forces under Rear Admirals Raymond A. Spruance and Frank J. Fletcher, assisted by planes based on Midway Island, intercepted and outfought a large enemy naval force in the vicinity of Midway, which the Japanese had intended to seize. This was another battle in which planes did all the attacking. The Japanese lost 4 carriers, a heavy cruiser, 3 destroyers, some 275 planes, at least 4,800 men, and suffered heavy damage among the remaining vessels of their fleet. American losses included on carrier, the Yorktown, a destroyer, about 150 planes, and 307 men. After the Japanese broke off the engagement, part of their task force moved northward and seized three of the Aleutian Islands. Japan's losses, both at the Coral Sea and Midway, did much to restore the balance of naval power in the Pacific, and the Japanese never fully recovered from the loss of many of their best naval pilots in the two battles.

Offensive Against Rabaul: First Phase. After the Battle of Midway, the Allies were able to launch a limited offensive to protect their line of communications and to prevent the Japanese from consolidating their gains. On 2 July 1942 the U.S. Joint Chiefs of Staff issued orders specifying that Rabaul, on the island of New Britain, would be taken. Rabaul was the main base in the Japanese Southeast Area and was well situated to support Japanese advances southward. JCS specified that Rabaul would be taken in three stages: first, the seizure of bases in the southern Solomons; second, the reoccupation of the remainder of the Solomons and the north coast of New Guinea as far as Lae and Salamaua; and third, the recapture of Rabaul itself and the rest of the Bismarck Archipelago. The JCS gave the commander of the South Pacific Area, Vice Admiral Robert L. Ghormley (after October 1942, Admiral William F. Halsey), control over the first stage of the offensive. Strategic direction of the second and third phases of the offensive was given to General MacArthur of the Southwest Pacific Area.

Guadalcanal. On 7 August 1942 the first stage of the offensive began with landings by a Marine division on Guadalcanal and nearby islands. The Japanese reacted vigorously. They inflicted a serious defeat on Ghormley's naval forces in the Battle of Savo Island (8 August 1942), landed large numbers of reinforcements on Guadalcanal, and ultimately lost strong ground, air and naval forces in a desperate effort to hold Guadalcanal. Six major naval engagements were fought off the island. Air battles raged almost daily until the end of October 1942. On shore the issue was in doubt for almost three months. Before the island was finally secured in February 1943, the United States had committed two Marine divisions, two Army divisions, and an additional Army regiment to the fight. Late in February 1943 an Army division was unopposed in taking the Russell Islands, 35 miles northwest of Guadalcanal. The Allies thus firmly established themselves in the Solomons.

Papuan Campaign. Having been repulsed in attempts to take Port Moresby in southeastern New Guinea by sea in May 1942 in the Battle of the Coral Sea, and again in August by the Australians at Milne Bay, the Japanese pushed a drive toward their objective over the Owen Stanley Mountains from the Buna-Gona area in southeastern New Guinea. When by mid-September the Japanese came within 30 miles of Port Moresby, MacArthur committed additional Australian troops to push the invaders back across the mountains. By mid-November the Japanese had been driven back to their positions on the north coast at Buna, Gona, and Savanna, where they received reinforcements from Rabaul and clung desperately to their beachhead. Two Australian divisions, one U.S. Army division, and a separate U.S. Army regiment had been committed to the fight before the fall of Gona (9 December), Buna (2 January 1943), and Sanananda (23 January). An outstanding achievement of the campaign was the air supply of the Allied ground forces.

Following the Papuan and Guadalcanal campaigns there was a five-month lull for ground forces while the Allies prepared for the second phase of the drive on Rabaul, but there was plenty of action on the sea and in the air. During this period the Japanese made a major effort to reinforce their positions in the Solomons and New Guinea. A large convoy sent to reinforce the Japanese position at Lae, New Guinea, was sighted by planes of the Allied Air Forces, Southwest Pacific Area (Lt. Gen. George C. Kenney commanding), and the Battle of the Bismarck Sea (1-3 March 1943) was the result. Some 335 Allied planes based on Papua, assisted in the mop-up phase by 8 motor torpedo (PT) boats, attacked the convoy and destroyed 12 ships (including 8 transports), some 3,000 men, and 20 to 30 planes. Allied losses in the three-day running battle were 5 planes. In waters of this area, shadowed by American planes, the Japanese never again risked a transport larger than a small coaster or a barge.

In April, and again in June 1943, Japanese carrier and Rabaul-based planes tried but failed to knock out Allied air and naval power in the Solomons and New Guinea. The loss of carrier planes and pilots during this air offensive further reduced the capabilities of the Japanese Combined Fleet whose commander, Admiral Isoroku Yamamoto, was shot down over Bougainville.

Offensive Against Rabaul: Second Phase. The second stage of the offensive against Rabaul began in late June 1943. The purpose of this operation was to reoccupy the remainder of the Solomons and the northern coast of New Guinea as far as Lae and Salamaua. MacArthur's forces landed on islands off eastern New Guinea and on the New Guinea coast northwest of Buna where they were to mike contact with an Australian division which was already fighting near Salamaua. The ground combat forces of MacArthur's command were by this time largely assigned to the U.S. Sixth Army, which had been activated on 25 January 1943 and which began operations in the Southwest Pacific Area in February 1943 under commend of Lt. Gen. Walter Krueger.

About the same time Sixth Army troops began their June offensive, Admiral Halsey's South Pacific forces, operating under MacArthur's strategic direction, landed on the island of New Georgia in the central Solomons. The object of these operations was to secure air bases to support further advances in a two-pronged drive up the Solomons and the New Guinea coast toward Rabaul.

New Georgia and Bougainville. The advance in the Solomons under Admiral Halsey's command started from Guadalcanal where air support was based on Henderson Field, and moved toward the Japanese air base at Munda on Near Georgia Island about 200 miles north. Landings on New Georgia began as early as 20 June 1943 when Marines, followed by Army forces the next day, landed at Segi Point and moved overland to take Viru Harbor on 1 July. There were various other landings on New Georgia, but the principal effort, with Munda as its objective, began on 10 June 1943 (D-Day for this phase of the operation) with a landing on Rendova Island, just off New Georgia and near Munda. From Rendova, Marine and Army forces invaded New Georgia and closed on the Japanese base at Munda, which fell after nearly six weeks of hard fighting on 5 August 1943. Another Japanese strong point at Bairoko Harbor, 8 miles north of Munda, fell on 25 August. Kolombangara was bypassed with the landing of Army, Marine, and New Zealand troops on Vella Lavella and Arundel Islands. There was considerable air and naval action, and the Japanese lost heavily in ships and planks as they first reinforced and then evacuated their island positions. It was October before the Allies had fully secured the island group.

The next major operation was an invasion of the island of Bougainville, which was approached by landings at Mono and Stirling in the Treasury Islands on 25-27 October 1943. A Marine division landed on the west coast of Bougainville at Empress Augusta Bay on 1 November 1943. The Marines were followed within the month by an Army division and replaced in the next month by another Army division. It was late November before the beachhead at Empress Augusta Bay was secure. This beachhead was all that was needed, and no attempt was made to capture the entire island. Allied planes neutralized enemy airfields in the northern part of the island, and the Allied command made use of its naval and air superiority to contain the Japanese garrison on Bougainville and cut its supply line to Rabaul by occupying the Green Islands (14 February 1944). Despite these measures, the Japanese maintained pressure against the beachhead, mounting an especially heavy but unsuccessful counterattack as late as March 1944. Success at Bougainville isolated all Japanese forces left in the Solomons. The Japanese sustained comparatively heavy air and naval losses during the campaign, which further crippled the Japanese Combined Fleet and had a vital effect on the balance of naval power in the Central Pacific.

New Guinea. During the campaign in the northern Solomons, Southwest Pacific forces had been pushing forward on the other prong of the offensive in New Guinea and western New Britain. The 5th Australian Division, with the help of a U.S. Army regiment, took Salamaua on 11 September 1943. Meanwhile, the 9th Australian Division and a U.S. Army Engineer Special Brigade had landed east of Lae on 4 September. The next day a regiment of U.S. Army paratroopers, conducting the first American airborne operation in the Pacific, flew from Port Moresby, jumped and captured Nadzab, northwest of Lae, after which the 7th Australian Division was flown into Nadzab. A coordinated attack by the 7th and 9th Australian Divisions resulted in the fall of Lae on 16 September. Lae was developed into a forward naval base while Nadzab became a major air base.

Allied forces next moved to take Finschhafen (2 October 1943) on the eastern end of the Huon Peninsula. MacArthur had hoped to trap the Japanese on this peninsula, but the survivors of Lae and Salamaua escaped overland to the north shore of the Huon Peninsula while those from Finschhafen withdrew along the coast. American and Australian troops fought more than three months, until mid-February 1944, in the New Guinea jungles before the Huon Peninsula was considered secure. Forces of both the South and Southwest Pacific were now in position for a final assault on Rabaul.

Offensive Against Rabaul: Third Phase. With the end of the second phase of the offensive against Rabaul the JCS changed their plans. They decided that seizure of Rabaul would be unnecessarily costly. The same results could be obtained by encircling Rabaul and neutralizing it by aerial bombardment, and by seizing a base for Allied use in the Admiralties. An air base in the Admiralties would support the westward drive along the north coast of New Guinea and support Central Pacific advances by long-range air reconnaissance; the Admiralties would also provide a major naval base for the Fifth Fleet of the Central Pacific. Despite the changed plans the seizure of western New Britain began on 15 December 1943 when Army units landed at Arawe, followed by a Marine landing at Cape Gloucester on 26 December. In mid-February 1944, New Zealand troops of Halsey's command took an air base on one of the Green Islands, east of Rabaul, and at the end of the month MacArthur's forces tightened the circle on Rabaul by landing in the Admiralty Islands. These islands eventually provided two heavy bomber fields as well as two fields for carrier-type planes, and Seeadler Harbor was developed into one of the largest naval bases in the Pacific. In the following three months Marine and Army forces completed the encirclement, and effectively isolated the 100,000-man Japanese garrison at Rabaul. This operation set the pattern of Allied operations in the Pacific for the rest of the war. Frontal attacks against strong Japanese positions were avoided if possible. Rather, Allied forces "leap-frogged" toward Japan, their leaps limited only by the range of land-based aircraft and the availability of carrier-borne planes. Bypassed Japanese positions were thereby left isolated and strategically impotent.

The Aleutians. Japanese seizure of Attu, Kiska, and Agattu of the Aleutian Islands in June 1942 was strategically unimportant, but the occupied islands did provide the Japanese with a base for raiding Alaska and limiting air and sea operations in the North Pacific. At the time of the seizure, the United States did not have available ships, planes, and troops to recapture the islands, but advanced airfields were established on Adak and Amchitka, in August 1942, from which American bombers attacked Kiska and Attu.

 Plans were made in the spring of 1943 to recapture Kiska and Attu. The operation was under the overall command of Vice Admiral Thomas E. Kinkaid, Commander, North Pacific. Rear Admiral Francis W. Rockwell commanded the assault force, and Maj. Gen. Albert E. Brown (who was replaced during the operations by Maj. Gen. Eugene M. Landrum) commanded the Army forces making the landing. It was eventually decided to bypass Kiska, and landings were made on Attu on 11 May 1943. Air and naval units supported the operation. The Japanese on Attu defended their position desperately, but they were destroyed almost to a man, and the fighting ended by 30 May.

On 15 August 1943 a powerful Allied amphibious force, including a U.S. infantry division and elements of the Royal Canadian Army commanded by Maj. Gen. Charles H. Corlett and a naval escort commanded by Admiral Kinkaid, assaulted the island of Kiska, where the Japanese had developed their largest base. To the surprise of the Allies, they found that the island had been secretly evacuated by the Japanese under cover of heavy summer fogs which had prevented aerial observation or interception. The Japanese had drawn their perimeter once more back to the Kuriles, and the Allies had opened another possible axis of advance toward Japan.

Operations in the China, Burma, India Theater. Japanese occupation of Burma in 1942 had cut off the last land route by which the Allies could deliver aid to the Chinese Government of Chiang Kai-shek. The only supply route available was the costly and dangerous "Hump" route for transport planes over the Himalayan. During 1943 the best the United States could do to support China was to keep alive Maj. Gen. Claire L. Chennault's Fourteenth U.S. Army Air Force in China, train two Chinese divisions airlifted out to Ramgarh in India, push a trickle of war supplies over the "Hump" and send a combat team of U.S. ground forces to support the Chinese in a projected plan to recapture Burma. Meanwhile, Allied leaders tried to persuade Chiang to attack the Japanese in China.

On 21 August 1943 provision was made by the CCS for setting up a supreme Allied command in Asia, named Southeast Asia Command (SEAC), with Admiral Lord Louis Mountbatten as Supreme Allied Commander. Mountbatten actually assumed his duties on 16 November 1943, at which time General Stilwell, Commanding General of CBI, became deputy commander and continued in this capacity until 21 October 1944 (he was succeeded in the position by Lt. Gen. Raymond A. Wheeler on 12 November 1944).

In the spring of 1944 the Allies were finally able to attempt the reconquest of Burma. A force under General Stilwell fought down the Hukawang Valley and reached the vicinity north of Myitkyina, a key communications center and Japanese stronghold, in May 1943. Meanwhile, the 5307th Composite Unit (Provisional), a reinforced U.S. Army regiment better known as "Merrill's Marauders," had circled and was attacking Myitkyina from the south. Japanese resistance and the onset of the monsoon season in June delayed completion of the operation until August. As another phase of the spring offensive, a British force (the so-called "Chindits") under Maj. Gen. Orde C. Wingate had made a successful airdrop near Kotha in March and proceeded to disrupt Japanese communications in central Burma. At the same time, farther to the south, a British Commonwealth force inflicted a considerable defeat on Japanese forces defending against a drive on Akyab, a port of the Bay of Bengal. Meanwhile, in western Burma, the Japanese had launched a powerful, and very nearly successful, counterattack toward Imphal and Kohima in eastern India. The British made a last-ditch stand in the vicinity of Kohima and, when reserves arrived, won a decisive victory at the end of June 1944. As the monsoon broke, the decimated Japanese force was in disorderly retreat back into the Jungles of Burma. By late summer of 1944 the Allies had cleared northern Burma, permitting construction of the Ledo (or Stilwell) Road and a fuel oil pipeline from India to China.

Until late 1944, securing a port and establishing airfields in southeastern China, from which bomber (B-29) raids could be launched on Japan, were considered essential parts of the strategic plan to defeat Japan. Opening a land supply route to China across Burma so that large numbers of Chinese Nationalist troops could be equipped was an essential prelude to the accomplishment of the strategic plan. Meanwhile, Chiang's Nationalist Government had failed to build up a strong military force and was engrossed with the revolt of China's Communists, led by Mao Tse-tung, who had gained control in North China. In September 1944 Japanese forces in China overran the airfields in South China and threatened areas slated for the construction of B-29 airfields. Progress of the offensive in the Pacific had by this time permitted a revision of Allied strategy, and it had become evident that islands in the Pacific which the Allies were capturing could be used to greater advantage than China as a springboard for an effective attack on Japan. In any event, President Roosevelt had displayed a growing disinterest in the China problem following his meeting with Chiang Kai-shek at Cairo in November 1943. Grandiose lend-lease plans for the eventual equipping and training of 30 Chinese divisions gradually evaporated. Differences with General Stilwell led Chiang in early October 1944 to ask that he be relieved as his Chief of Staff. Stilwell left China in late October and subsequently became Commanding General of the Army Ground Forces in the United States.

Upon Stilwell's departure the American administrative area CBI was separated into the U.S. Forces, China Theater (USFCT) and U.S. Forces, India-Burma Theater (USFIBT). These commands were established on 24 October 1944. Lt. Gen. Daniel I. Sultan was named (31 October) commanding general of the USFIBT, and Maj. Den. Albert C. Wedemeyer became (27 October) commanding general of the USFCT. Wedemeyer also took over Stilwell's position as Chief of Staff to Chiang Kai-shek.

General Wedemeyer, with the aid of an American cadre, endeavored to reorganize and train Chiang's forces for a drive to the coast, but that drive never came off. China was a disappointment, and the only aim of Allied strategy during the last year of the war was to keep Chinese resistance alive in order to distract Japanese forces in that area.

Operations in Burma during the last year of the war were largely a British show. Actually, the British were more interested in recovering Singapore than in taking Burma or helping China, but American control of lead-lease, combined with an American policy that continued to back Chiang Kai-shek more or less dictated the reconquest of Burma.

The British would have preferred to accomplish the reconquest of Burma from the south, beginning with a seaborne assault on Rangoon, but demands on shipping for European and Pacific operations precluded such a plan. Consequently, the British attacked from India across the Irrawaddy River to Mandalay and then south to Rangoon. They experienced tremendous difficulties because of the terrain and the resistance of crack Japanese troops. Supply by air was essential to the success of operations. Mandalay was captured after a prolonged fight in mid-March 1945. From then on progress to the south was relatively fast, and the reconquest of Burma was completed for practical purposes with the capture of Rangoon on 3 May 1945. Except for five Chinese divisions and a mixed American and Chinese brigade known as the Mars Task Force (replacing "Merrill's Marauders"), Allied forces in Burma consisted of British and British Commonwealth forces.

Drive to the Philippines. The campaigns against the Aleutians and Rabaul had stopped the Japanese drive and secured bases for advances on Japan. The task of Pacific planners was now to devise ways of bringing to bear on Japan itself, as quickly and effectively as possible, the increasing but still limited means available to them. The best way to cut communications to the south was to gain control of the South China Sea, and the objective chosen for this purpose was a triangle formed by the south China coast, Taiwan, and Luzon. It was decided that the best way to reach this strategic triangle was by concentrating Allied resources on approaches from the Pacific, since American production was beginning to produce enough carriers and aircraft to make such an approach possible, and by this time it was evident that an approach through Burma and China was not feasible.

The first step in securing control of the strategic triangle was to gain a foothold in the southern or central Philippines. To reach the Philippines the Allies used two routes of advance: one through the central Pacific Area via the Gilberts, Marshalls, Marianas, Carolines, and Palaus; the other through the Southwest Pacific Area via the north coast of New Guinea. Once the Marianas were taken, it would be possible to use them as bases from which the new long-range B-29 bombers could strike at the heart of Japan. An advantage of the second route urged by MacArthur was that it would provide for land-based air cover along the way. The double-pronged advance had the merit of keeping Japanese forces divided and of providing opportunities for surprise.

In Nimitz' Central Pacific Area, although Army forces were used, they were not organized in a field army. They were subject for supply and administration to the U.S. Army Forces in Central Pacific Area (USAFICPA), a command established on 14 August 1943 under Lt. Gen. Robert C. Richardson, Jr., who was concurrently Commanding General of the Hawaiian Department. The primary mission of this Army command was training. On 1 August 1944 USAFICPA was superseded by the U.S. Army Forces, Pacific Ocean Areas (USAFPOA) under which all U.S. Army forces previously assigned to the Central and South Pacific Areas were consolidated. General Richardson was retained as commander of the USAFPOA.

Central Pacific. The advance through the Central Pacific got under way in November 1943 with the seizure of two islands, Tarawa and Makin in the Gilberts. Marines landed on Tarawa on 21 November and took the island in a four-day fight at a cost to the Marines of some 3,000 casualties. Army troops overwhelmed the small Japanese garrison on Makin between 20 and 24 November 1943.

During January and February 1944, Admiral Nimitz proceeded to positions in the central and western Marshalls. The principal islands taken were Kwajalein, which was invaded by an Army force on 1 February, and the islands of Roi and Namur, which were invaded by Marines on 3 and 6 February. From Kwajalein a naval task force, moving west 340 miles with a regiment each of Marines and infantry, captured a Japanese air base on Engebi in the Eniwetok Atoll on 17-19 February 1944. Meanwhile, on 16 February, Nimitz had launched a massive carrier raid on Truk in the central Carolines, long considered Japan's key bastion in the central Pacific. This raid revealed that the Japanese had virtually abandoned Truk as a naval base, and a plan to assault that atoll in June was abandoned. Instead, Nimitz drew up plane for an invasion of the Marianas in June, to be followed in September by an advance into the western Carolines.

Approach to the Philippines. The advance along the southern prong aimed at the Philippines got under way in April 1944. Having by then secured the Admiralties. MacArthur now made a long leap, bypassing Japanese concentrations at Wewak and Hansa Bay, and secured beachheads at points along 175 miles of the northern New Guinea coast. On 22 April Army forces landed at Tanahmerah Bay, Aitape, and Humboldt Bay. Within four days airfields at the three beachheads were in American hands. A large base was established at Hollandia in Dutch New Guinea. Although fighting continued in some of the captured areas for some time, MacArthur in April 1944 wee already two months ahead of schedule. Australian forces eventually assumed a major part of the responsibility for reducing the bypassed areas. Covered by planes at Hollandia, Army forces next leaped 125 miles farther west to land, on 17 May, on the New Guinea coast opposite Wakde Island, which they invaded the following day to secure the Japanese airfield on the island. On 27 May another amphibious force landed on Biak Island, about 900 miles southeast of the Philippines. The Japanese defenders of Biak fought desperately to retain the island, and General Krueger, the U.S. Sixth Army Commander, did not declare the operation over until 20 August 1944.

The Japanese made a determined effort to reinforce Biak Island. Early in June they assembled sufficient naval strength to destroy naval units under MacArthur's control and sent about half their land-based aircraft in the Carolines and the Marianas to airfields in western New Guinea, where they were within easy range of Biak. No sooner had this redeployment of naval and air forces been accomplished than the Japanese learned of the presence of the U.S. naval force in the Marianas.

Admiral Nimitz invaded the Marianas in June 1944. Amphibious assaults were made on Saipan on 15 June, on Guam on 20 July, and on Tinian on 23 July 1944. All three islands were strongly garrisoned by Japanese troops who contested every yard of ground. Loss of Saipan precipitated a political crisis in Tokyo and brought about the fall of the Tojo Cabinet. The Japanese sallied forth to offer battle to the U.S. Pacific Fleet. They hastily reassembled their fleet from Biak and the Philippines and sailed north to defend the Marianas area, but lack of land-based air support made it impossible to surprise the U.S. naval contingents under Admiral Spruance. In a massive air battle that took place on 19 June, 4 days after landings on Saipan, the Japanese lost more than 400 planes to an American loss of less than 30. Stripped of carrier planes, the Japanese fleet fled westward, but American planes in pursuit were able to sink several vessels, including three carriers. During this engagement, known as the Battle of the Philippine Sea, only three American ships were damaged. This victory paved the way for eventual success in the Marianas, and provided a demonstration of the interdependence of operations in the Southwest and Central Pacific Areas.

MacArthur's and Nimitz' forces continued westward from Biak and the Marianas. On 2 July 1944 American troops had landed on Noemfoor Island, 90 miles beyond Biak, and near the end of the month other troops had pushed on to the western tip of New Guinea. With the capture of Morotai Island in mid-September, MacArthur was at last in position to make his return to the Philippines. Except for an abortive attack in mid-July on Aitape by Japanese troops that had been bypassed at Wewak, and mopping-up operations in other areas, troops of the Southwest Pacific Command spent the next weeks in preparation for reconquest of the Philippines.

In the Central Pacific, the Palaus were next to be attacked with a Marine landing on 15 September on Peleliu Island, where heavy fighting ensued and where organized resistance lasted until 26 November. Two days after the initial landings on Peleliu an Army division assaulted Angaur Island (17 September) There organized resistance lasted until 21 October.

During this period a new army made its appearance in the Southeast Pacific and took over a share of the enormous operational, administrative, and logistic responsibilities which had been carried by Sixth Army alone. The U.S. Eighth Army, activated on 10 June 1944, arrived in New Guinea in August and set up headquarters in Hollandia where Lt. Gen. Robert L. Eichelberger assumed command on 7 September 1944.

Reconquest of the Philippines. In the Philippines the principal objective had been Luzon since it was on one of the corners of the so-called strategic triangle. Since it was presumed that the Japanese had massed their principal ground, air, and naval strength in Luzon, United States strategists had planned to gain a foothold first in southernmost Mindanao, then move to Leyte, and finally to Luzon after air supremacy had been gained over that area. But when naval reconnaissance in September 1944 revealed little Japanese activity in the Philippines, Admiral Halsey proposed landing directly on Leyte in October. This change of strategy was quickly approved by the U.S. Chiefs of Staff, who were at that time attending the second Quebec Conference. Strategically the plan was brilliant, because it would force the Japanese to split their forces in the Philippines and practically force the Japanese Combined Fleet to come out in the open to meet the threat.

The amphibious assault on Leyte took place on 20 October 1944 with four divisions of the U.S. Sixth Army going in abreast. The invading force included the XXIV Corps from the Central Pacific. Initial opposition was light, but the Japanese who had expected to make their main stand on Luzon decided to shift their remaining air and naval might against the U.S. forces in Leyte. They were also successful for a tame in sending large numbers of ground reinforcements to Leyte, and the Sixth Army found itself engaged in a major struggle.

As had been anticipated, the attack on Leyte presented the Japanese navy with a challenge it could not ignore. Gathering together its remaining strength, the Japanese Combined Fleet converged on Leyte Gulf in three columns, and for a time seriously threatened the success of the whole Leyte operation. Actually, the sea battle was a series of engagement's lasting from 23 to 26 October. In the end, Japan's fleet was almost completely destroyed, and for the rest of the war Allied naval forces were in virtual control of the surface of the Pacific.

Two months of heavy ground fighting took place in Leyte before American troops had secured parts of the island necessary for air and logistical bases, before the Army Air Forces had gained air superiority, and before naval And air forces had stopped Japanese reinforcing operations. Late in December General MacArthur announced that thereafter the U.S. Eighth Army would assume combat responsibility for the Leyte-Samar area.

Long before invasion of the Philippines, the question had arisen among United States strategists as to what the next target would be. Originally the plan had been to bypass the Philippines and to conduct the B-29 strategic bombing program from bases in China. Subsequently, plans were made for the conquest of Taiwan as an additional base for B-29's after a foothold had been gained in the Philippines. With the overrunning of airfields and planned sites for B-29's by the Japanese in China, and with the Marianas available as a base for strategic bombing operations, a change of plans was indicated. United States military strategists became embroiled in a behind-the-scenes debate as to what the next move should be. The outcome of this controversy was a decision on the part of the JCS to make Luzon the next target, discard the plan to bomb Japan from bases in China, and bypass Taiwan. Troops scheduled to take Taiwan were to be used to invade Okinawa and other islands in the Ryukyus beginning in March 1945.

In keeping with the plan, the U.S. Sixth Army made a massive amphibious assault on Luzon along the shores of the Lingayen Gulf on 9 January 1945. The Japanese commander, General Tomoyuki Yamashita, did not intend to defend the Central Plains-Manila Bay area, but sought only to pin down major elements of MacArthur's forces in order to delay Allied progress to Japan. Nevertheless, strong Japanese forces, primarily naval, disregarded Yamashita's plan and held out in Manila. A powerful American force drove down the central valley from the Gulf of Manila, which fell in March after a month of bitter fighting. Yamashita concentrated his forces in three mountainous strongholds where they could conduct a protracted defense. Except for one strong pocket in the mountains of north-central Luzon, where the Japanese were still fighting when the war ended, organized Japanese resistance in Luzon was overcome by the end of May. Meanwhile, the U.S. Eighth Army had completed the operation on Leyte, subdued the Japanese in the southern Philippines in a series of amphibious attacks, and conducted the mop-up phase of operations on Luzon.

Capture of the Marianas had brought Japan within reach of the Army Air Forces' huge new bomber, the B-29, which was able to make a nonstop flight of the 1,400 miles to Tokyo and back. Construction of airfields to accommodate B-29's began in the Marianas before the shooting had stopped, and in late November 1944 the strategic bombing of Japan began. Destruction wrought on the cities of Japan was enormous. But, as in Germany, postwar surveys revealed that strategic bombing had not been of decisive effect in crippling industrial production. Much of Japan 'e industrial plant was intact, but was rendered idle by the serious shortage of raw materials which the Allied naval blockade had produced. Although thousands of Japanese civilians were killed and literally millions were made homeless by air bombing, only a relatively small percentage of Japan's industrial facilities were destroyed, not enough to affect seriously Japanese capacity to resist.

Iwo Jima and Okinawa. Iwo Jima, a barren volcanic island midway between Saipan and Japan, was considered desirable as an emergency base for B-29's flying to and from Japan. Cancellation of plans to take Taiwan provided an opportunity for the Central Pacific forces to undertake the hitherto unscheduled conquest of Iwo Jima, and the JCS directed Admiral Nimitz to take the island in February. Two Marine divisions made the assault on 19 February, touching off a month of as severe fighting as American forces experienced during World War II. A third Marine division evenly had to be thrown into the battle as 23,000 Japanese, firmly entrenched in terrain that gave every advantage to the defenders, exacted a price of some 20,000 American casualties for the tiny island. The campaign came to an official end on 16 March 1945.

The invasion of the Ryukyus was made by troops of the U.S. Tenth Army, which had been activated on 20 June 1944 with Lt. Gen. Simon B. Buckner, Jr., as commanding general. The Ryukyus campaign began on 26 March 1945 with the capture of small islands near Okinawa, where forward naval bases were established. An amphibious assault on Okinawa took place on 1 April, and the fighting lasted until June. Here, for the first time, Americans were invading what the Japanese defenders considered their home soil, and the defense was fanatic in the extreme. American troops suffered heavy casualties, and the Navy, too, had heavy personnel losses as Japanese suicide flyers, the Kamikazes, sank some 25 American ships and damaged 165 others in a desperate attempt to save the Ryukyus. Among the nearly 35,000 American casualties were General Buckner, who was killed on 18 June. He was succeeded by Maj. Gen. Roy S. Geiger, who was in turn succeeded by General Joseph W. Stilwell, who arrived to assume command of the Tenth Army on 22 June 1945.

Capture of the Ryukyus gave Allied naval and air forces excellent bases within 700 miles of Japan proper. Throughout June and July, Japan was subjected to increasingly intensive air attack and even to naval bombardment.

Allied forces were now in position for the final assault. In preparation for the invasion of Japan, a reorganization of U.S. Pacific forces had been effected on 3 April 1945, in which General MacArthur was given command of all Army forces and Admiral Nimitz of all naval forces. MacArthur's new command was designated U.S. Army Forces, Pacific (AFPAC). The war ended before the reorganization could have any effect on operations.

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