Battle of Okinawa
Okinawa was the largest amphibious invasion of the Pacific campaign and the last major campaign of the Pacific War. More ships were used, more troops put ashore, more supplies transported, more bombs dropped, more naval guns fired against shore targets than any other operation in the Pacific. More people died during the Battle of Okinawa than all those killed during the atomic bombings of Hiroshima and Nagasaki. Casualties totaled more than 38,000 Americans wounded and 12,000 killed or missing, more than 107,000 Japanese and Okinawan conscripts killed, and perhaps 100,000 Okinawan civilians who perished in the battle.
The battle of Okinawa proved to be the bloodiest battle of the Pacific War. Thirty-four allied ships and craft of all types had been sunk, mostly by kamikazes, and 368 ships and craft damaged. The fleet had lost 763 aircraft. Total American casualties in the operation numbered over 12,000 killed [including nearly 5,000 Navy dead and almost 8,000 Marine and Army dead] and 36,000 wounded. Navy casualties were tremendous, with a ratio of one killed for one wounded as compared to a one to five ratio for the Marine Corps. Combat stress also caused large numbers of psychiatric casualties, a terrible hemorrhage of front-line strength. There were more than 26,000 non-battle casualties. In the battle of Okinawa, the rate of combat losses due to battle stress, expressed as a percentage of those caused by combat wounds, was 48% [in the Korean War the overall rate was about 20-25%, and in the Yom Kippur War it was about 30%]. American losses at Okinawa were so heavy as to illicite Congressional calls for an investigation into the conduct of the military commanders. Not surprisingly, the cost of this battle, in terms of lives, time, and material, weighed heavily in the decision to use the atomic bomb against Japan just six weeks later.
Japanese human losses were enormous: 107,539 soldiers killed and 23,764 sealed in caves or buried by the Japanese themselves; 10,755 captured or surrendered. The Japanese lost 7,830 aircraft and 16 combat ships. Since many Okinawan residents fled to caves where they subsequently were entombed the precise number of civilian casualties will probably never be known, but the lowest estimate is 42,000 killed. Somewhere between one-tenth and one-fourth of the civilian population perished, though by some estimates the battle of Okinawa killed almost a third of the civilian population. According to US Army records during the planning phase of the operation, the assumption was that Okinawa was home to about 300,000 civilians. At the conclusion of hostilities around 196,000 civilians remained. However, US Army figures for the 82 day campaign showed a total figure of 142,058 civilian casualties, including those killed by artillery fire, air attacks and those who were pressed into service by the Japanese army.
By April, 1945 German resistance in the European Campaign was on the verge of collapse, but the Empire of Japan continued to defiantly resist American advances across the Pacific. Strategically located some 400 miles south of Japan, possession of Okinawa would enable the Allies to cut Japan's sea lines of communication and isolate it from its vital sources of raw materials in the south. If the invasion of Japan proved necessary, Okinawa's harbors, anchorages, and airfields could be used to stage the ships, troops, aircraft, and supplies necessary for the amphibious assault. The island had several Japanese air bases and the only two substantial harbors between Formosa and Kyushu.
The outbreak of hostilities in China during the 1930s initially had little impact on the inhabitants of the Ryukyu Islands, a chain running southwest from the Japanese home island of Kyushu toward Taiwan. Despite its size, of approximately 480 square miles and its population of perhaps 500,000, Okinawa had neither surplus food nor a great deal of industry to assist the Japanese effort. Its harbor facilities were unsuitable for large warships. The island's main contribution to the war effort lay in the production of sugarcane, which could be converted into commercial alcohol for torpedoes and engines.
From the first days of the Asia-Pacific war, Okinawa was fortified as the location of airbases and as the frontline in the defense of mainland Japan. Land and farms were forcibly expropriated throughout Okinawa and the Imperial Japanese Army began the construction of airbases.
By late October 1944, Okinawa, in the Ryukyu Island chain, had been targeted for invasion by Allied forces. This invasion -- code named Operation Iceberg --- would see the assembling of the greatest naval armada ever. Admiral Raymond A. Spruance's 5th fleet was to include more than 40 aircraft carriers, 18 battleships, 200 destroyers and hundreds of assorted support ships. Some 1,300 US ships surrounded the island. Of those, 365 were amphibious ships. Over 182,000 troops would make up the assault, planned for 01 April 1945, Easter Sunday. On 29 September 1944 B-29 bombers conducted the initial reconnaissance mission over Okinawa and its outlying islands. On 10 October 1944 nearly two hundred of Admiral Halsey's planes struck Naha, Okinawa's capital and principal city, in five separate waves. The city was almost totally devastated. The American war against Japan was coming inexorably closer to the Japanese homeland.
In mid-March 1945, the American fleet of over 1,300 ships gathered off Okinawa for the naval bombardment The first kamikaze attacks of the Okinawan campaign began on 18 March 1945. On 21 March, the first baka or piloted, suicide rocket bombs, were spotted below Japanese "Betty" bombers.
The invasion began on 01 April 1945 when 60,000 troops (two Marine and two Army divisions) landed with little opposition. The day began and ended with the heaviest concentration of naval gunfire ever expended to support an amphibious landing. Gathered off the invasion beaches were 10 older American battleships, including several Pearl Harbor survivors-the USS Tennessee, Maryland, and West Virginia-as well as 9 cruisers, 23 destroyers and destroyer escorts, and 117 rocket gunboats. Together they fired 3,800 tons of shells at Okinawa during the first 24 hours. Okinawans had long been resigned to the severe typhoons that sweep their land, but nothing in their experience prepared them for the tetsu no bow -- the "storm of steel" -- as one Okinawan characterized the assault on the island. At 0830 the 7th and 96th Infantry Divisions of the XXIV Corps and the 1st and 6th Marine Divisions of the III Amphibious Corps crossed the Hagushi beaches, with 16,000 troops landing unopposed in the first hour. By nightfall more than 60,000 were ashore.
Although Okinawa was strongly defended by more than 100,000 troops, the Japanese chose not to defend the beaches. The uncontested landings of 01 April were part of the overall Japanese strategy to avoid casualties defending the beach against overwhelming Allied firepower. A system of defense in depth, especially in the southern portion of the island, would permit the 100,000-man-strong Japanese 32nd Army under General Ushijima to fight a protracted battle that would put both the attacking amphibious forces and naval armada at risk. The Japanese dug into caves and tunnels on the high ground away from the beaches in an attempt to negate the Allies' superior sea and air power.
The battle proceeded in four phases: first, the advance to the eastern coast (April 1-4); second, the clearing of the northern part of the island (April 5-18); third, the occupation of the outlying islands (April 10 - June 26); and fourth, the main battle against the dug in elements of the 32nd Army which began on 06 April and did not end until 21 June. Although the first three phases encountered only mild opposition, the final phase proved extremely difficult because the Japanese were well entrenched in and naval gunfire support was ineffective.
On April 6-7, the first use of massed formations of hundreds of kamikaze aircraft called kikusui, or "floating chrysanthemum", for the imperial symbol of Japan, began. By the end of the Okinawan campaign, 1,465 kamikaze flights were flown from Kyushu to sink 30 American ships and damage 164 others. The Japanese had devised a plan to load-up high-speed motorboats with high explosives and have them attack the American Fleet. The boats were hidden in caves up rivers and pulled inside along railroad tracks. The plan never was carried out, however.
The Japanese battleship, Yamato, the largest warship ever built accompanied by the light cruiser Yahagi and eight destroyers, was dispatched to Okinawa on 06 April 1945, with no protective air cover. So badly depleted was the Japanese fleet by this time, Yamato was reported to carry only enough fuel for a one-way trip to Okinawa. Her mission: beach herself at Okinawa and fight until eliminated. The American submarine Hackleback tracked her movements and alerted carrier-based bombers. Vice Admiral Marc Mitscher launched air strikes on April 7 at 10 a.m. The first hits on Yamato were claimed by the carrier Bennington. San Jacinto planes sunk the destroyer Hamakaze, with a bomb and torpedo hit. The light cruiser Yahagi was hit by bombs and went dead in the water. For the next two hours, the Japanese force was under constant attack. Yamato took 12 bombs and seven torpedo hits within two hours, finally blowing up and sinking. Three accompanying destroyers were so badly damaged they had to be scuttled. Four remaining destroyers could not return to Japan. Of Yamato's crew of 2,747, all but 23 officers and 246 enlisted men were lost. Yahagi lost 446; Asashimo lost 330; the seven destroyers, 391 officers and men. There were few Japanese survivors. Losses to the Americans were 10 planes and 12 men. This was the last Japanese naval action of the war.
By 19 April soldiers and marines of the US Tenth Army under LGEN Buckner USA were engaged in a fierce battle along a fortified front which represented the outer ring of the Shuri Line. This fighting contrasted dramatically with the unopposed landings and initial rapid advances of the previous weeks. The Shuri defenses were deeply dug into the limestone cliffs and boasted mutually supporting positions as well as a wealth of artillery of various calibers. As the battle dragged on, American casualties mounted. This delay in securing the island caused great consternation among the naval commanders since the fleet of almost 1,600 ships was exposed to heavy enemy air attacks. The most damage from the Japanese attacks came from operation Ten-Go (Heavenly Operation) which employed mass deployment of the fearsome kamikaze.
American losses mounted as soldiers and marines assaulted points on the Shuri line with the deceptive names of Sugar Loaf, Chocolate Drop, Conical Hill, Strawberry Hill, and Sugar Hill. During the course of the battle American forces were informed of two pieces of dramatic news, one tragic and the other joyous. The first was the death of president Franklin Roosevelt on 12 April and the latter the surrender of Nazi Germany on 8 May.
By the end of May monsoon rains which turned contested slopes and roads into a morass exacerbated both the tactical and medical situations. The ground advance began to resemble a World War I battlefield as troops became mired in mud and flooded roads greatly inhibited evacuation of wounded to the rear. Troops lived on a field sodden by rain, part garbage dump and part graveyard. Unburied Japanese bodies decayed, sank in the mud, and became part of a noxious stew. Anyone sliding down the greasy slopes could easily find their pockets full of maggots at the end of the journey.
Heavy pressure on the Shuri Line finally convinced GEN Ushijima to withdraw southward to his final defensive positions on the Kiyamu Peninsula. His troops began moving out on the night of 23 May but were careful to leave behind rear guard elements that continued to slow the American advance. Japanese soldiers too wounded to travel were given lethal injections of morphine or simply left behind to die. By the first week of June, US forces had captured only 465 enemy troops while claiming 62,548 killed. It would take 2 more weeks of hard fighting and an additional 2 weeks of "mopping up " operations pitting explosives and flamethrowers against determined pockets of resistance before the battle would finally be over. The so called "mopping up" fighting between 23 and 29 June netted an additional 9,000 enemy dead and 3,800 captured. Among the Japanese, the incidence of suicide soared during the final days. An examination of enemy dead revealed that, rather than surrender, many had held grenades against their stomachs, ending their personal war in that manner. General Ushijima committed ritual suicide (hara-kiri) on 16 June, convinced that he done his duty in service to the Emperor.
The document ending the Battle of Okinawa was signed on what is now Kadena Air Base on 07 September 1945. Long before the firing stopped on Okinawa, engineers and construction battalions, following close on the heels of the combat forces, were transforming the island into a major base for the projected invasion of the Japanese home islands.
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