Battle of Okinawa

• 1. Introduction

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  The Battle of Okinawa began on the 1st of April 1945, when American forces launched the largest amphibious assault ever attempted in the Pacific Theater of World War II. They called it Operation Iceberg. The island they were storming lay just 340 miles from the Japanese home islands, and everyone on both sides understood what that meant.

  The fighting that followed lasted 82 days. It earned a nickname in two languages: "typhoon of steel" in English, and "tetsu no bōfū" in Japanese. Both names pointed to the same reality: a ferocity of combat so extreme that military historian George Feifer would later describe it as the largest land-sea-air battle in history.

  By the time organized resistance ended on the 21st of June 1945, the Cornerstone of Peace monument at the Okinawa Prefectural Peace Memorial Museum would record 242,046 names. Those names included 149,634 Okinawans, 77,823 Imperial Japanese soldiers, and 14,010 Americans. What happened on that island, and why it mattered so deeply, is the story we're about to follow.

• 2. The Forces Assembled

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  Lieutenant General Simon Bolivar Buckner Jr. commanded a force unlike anything previously assembled in the Pacific. His Tenth Army brought together soldiers and Marines under one command, with its own Tactical Air Force, a joint Army-Marine structure that had no precedent in the war.

  At the start of the battle, Buckner had 182,821 personnel under his command. That figure included over 103,000 Army soldiers, more than 88,000 Marines, and 18,000 Navy personnel, most of them Seabees and medical staff. The invasion fleet carried 18 battleships, 27 cruisers, 177 destroyers and destroyer escorts, and 39 aircraft carriers. Total aircraft provided by the Navy, Marines, and Army Air Force exceeded 3,000 over the course of the campaign.

  A British Commonwealth contingent added its own weight. British Task Force 57, with four large and six escort carriers, took up position off the Sakishima Islands to protect the southern flank, and it brought 251 British naval aircraft along with Australian, New Zealand, and Canadian ships and crews.

  Waiting for them on Okinawa was Lieutenant General Mitsuru Ushijima's Thirty-Second Army. It consisted of between 67,000 and 77,000 regular soldiers, about 9,000 Imperial Japanese Navy troops at Oroku Naval Base, and 39,000 drafted Ryukyuan civilians. That last group included 24,000 hastily assembled rear militia called Boeitai and 15,000 non-uniformed laborers. Ushijima's staff had calculated that each American division carried five or six times the firepower of a Japanese division. Their strategy, shaped partly by Colonel Hiromichi Yahara, leaned toward defense over offense.

• 3. Kamikaze

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  On the 6th of April 1945, about 400 Japanese planes launched from Kyushu and struck the Allied fleet. It was the first large coordinated kamikaze assault of the campaign, and it set the pattern for what was coming.

  Between the 6th of April and the 22nd of June, the Japanese flew 1,465 kamikaze aircraft in large-scale attacks from Kyushu, plus 185 individual kamikaze sorties from Kyushu and 250 more from Taiwan, then called Formosa. Seven major kamikaze attacks were launched in the period between the American landing and the 25th of May, involving more than 1,500 planes in total. The Japanese had used kamikaze tactics since the Battle of Leyte Gulf, but Okinawa was the first time they became a fully institutionalized element of defensive strategy.

  The results were staggering. From the 26th of March to the 30th of April alone, 20 American ships were sunk and 157 were damaged by enemy action. By the campaign's end, 36 Allied ships had been sunk, and 368 more were damaged, including 120 amphibious craft. The US Navy's dead exceeded its wounded for the first time in the war: 4,907 killed against 4,874 wounded.

  An American observer recorded watching the attacks with a strange detachment: "We watched each plunging kamikaze with the detached horror of one witnessing a terrible spectacle rather than as the intended victim. We forgot self for the moment as we groped hopelessly for the thought of that other man up there."

  Admiral Spruance's flagship was hit in March and again in May, forcing him to transfer ships twice. Fast Carrier Task Force commander Vice Admiral Marc Mitscher survived a strike on his flagship USS Bunker Hill on the 11th of May only because he happened to be standing yards away from where the kamikaze hit. Three of his staff officers were killed, eleven of his enlisted staff died, and the strike destroyed his flag cabin, his uniforms, and all his personal possessions. Three days later, his new flagship was also struck, and he had to change flagships again.

  The strain on the fleet commanders was so severe that Admiral Chester Nimitz took the unprecedented step of rotating the principal naval commanders out of duty to rest and recover. The fleet changed designation mid-campaign: it began as the 5th Fleet under Spruance and ended as the 3rd Fleet under Admiral Halsey.

• 4. Steel and Mud

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  Tenth Army swept the north of Okinawa with relative ease. The 6th Marine Division reached Hedo Point, the northernmost tip of the island, by the 13th of April after sealing off the Motobu Peninsula just days before. Heavy fighting cleared the key terrain feature of Mount Yaedake on the 18th of April.

  The south was different. The 96th Infantry Division ran into fierce resistance near Cactus Ridge, fortified positions east of Highway No. 1 about 5 miles northwest of Shuri. The 7th Infantry Division hit similar resistance at a rocky pinnacle dubbed "The Pinnacle" southwest of Arakachi. By the 8th of April, Americans had cleared these positions at a cost of over 1,500 battle casualties while killing or capturing about 4,500 Japanese. And those had been mere outposts.

  The main Japanese defensive line centered on Shuri, and its approaches were brutally fortified. At Kakazu Ridge, Japanese soldiers hid in caves and fought tenaciously from prepared positions. An American tank assault on the 19th of April, launched after a barrage of 324 guns, the largest ever in the Pacific Ocean Theater, failed to break through. The XXIV Corps suffered 720 casualties in a single day, and 22 tanks were lost in one failed flanking attempt.

  On the 13th of May, troops of the 96th Infantry Division and 763rd Tank Battalion captured Conical Hill, rising 476 feet above the Yonabaru coastal plain and held by about 1,000 Japanese. The 1st and 6th Marine Divisions fought simultaneously for Sugar Loaf Hill on the opposite coast. Together, these captures unraveled the Shuri Line.

  By late May, monsoon rains had turned contested terrain into a morass. A Marine Corps account described troops living "on a field sodden by rain, part garbage dump and part graveyard." Unburied bodies, Japanese and American alike, decayed in the mud. Troops sliding down hillsides sometimes reached the bottom with their pockets full of maggots. Combat fatigue cases from Okinawa exceeded those from any other battle in the Pacific during World War II.

• 5. Children at War

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  One of the least visible facts of the battle is who the Japanese army put in the fight. An ordinance of the Ministry of the Army mobilized 1,780 schoolboys aged 14 to 17 into front-line service as an Iron and Blood Imperial Corps, known in Japanese as the Tekketsu Kinnōtai.

  The mobilization was not technically by law. The ordinances framed the students as volunteer soldiers. In practice, military authorities ordered schools to force nearly all students to "volunteer," and sometimes officials forged the necessary documents to make it legal. Female students from the Himeyuri schools were organized into nursing units, still exposed to the full violence of combat despite their non-combat role.

  Among the 21 male and female secondary schools that made up the student corps, 2,000 students died on the battlefield. About half of the Tekketsu Kinnōtai were killed outright, some in suicide bomb attacks against American tanks, others in guerrilla operations.

  These were not soldiers by any meaningful definition. They were teenagers pressed into a collapse and sent into positions that experienced troops could not hold. Their deaths are recorded individually at the Cornerstone of Peace monument, which as of 2023 listed 242,046 names.

• 6. Okinawan Civilians

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  US Army planners estimated Okinawa held about 300,000 civilians before the battle. Those civilians became trapped between two armies, and both caused them harm.

  The Imperial Japanese Army used Okinawans as human shields, confiscated their food, and executed those who hid it. Japanese soldiers also killed about 1,000 people who spoke in the Okinawan language, to suppress suspected spying. Civilians were forced out of their shelters and into the open, where artillery, disease, and starvation killed them. The official US Tenth Army count recorded 142,058 recovered enemy bodies, with an estimate that about 42,000 were non-uniformed civilians killed in the crossfire.

  As Japanese defeat became apparent, thousands of civilians committed mass suicide. Japanese soldiers had told locals that victorious American troops would torture and rape them. Some civilians threw themselves from the southern cliffs where the Peace Museum now stands. Ryukyu Shimpo, one of the two major Okinawan newspapers, reported in 2007 that many Okinawans testified the Japanese Army had directed them to commit suicide and that some had been handed grenades by soldiers. Survivors later said the indoctrination of their education system, which had taught Okinawans to become "more Japanese than the Japanese," was also to blame.

  American Military Intelligence Corps translators such as Teruto Tsubota managed to convince many civilians not to kill themselves. A study titled Islands of Discontent by Mark Selden states that the Americans "did not pursue a policy of torture, rape, and murder of civilians as Japanese military officials had warned." Many Okinawans, the source notes, "were often surprised at the comparatively humane treatment they received from the American enemy."

  The 32nd Army's retreat to the Kiyan Peninsula in the final weeks brought the worst killing to the south. Nearly 30,000 Japanese personnel moved into that final defense line, and the fighting there caused the greatest concentration of civilian deaths in the entire campaign.

• 7. Command Lost

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  Shuri Castle fell on the 29th of May 1945. The 1st Battalion, 5th Marines had occupied high ground 700 yards east of the castle and reported it appeared undefended. At 10:15, Company A moved in and took it. A Confederate flag was raised over the castle that day before General Buckner ordered it replaced by a US flag three days later. Buckner was himself the son of a Confederate general.

  The Japanese retreat south was skillful. Ushijima moved nearly 30,000 personnel under cover of monsoon storms and artillery harassing fire, establishing a final defense line on the Kiyan Peninsula.

  On the 18th of June, four days before the campaign officially ended, General Buckner was killed by Japanese artillery fire while observing operations from a forward post. Lethal slivers of coral tore through him. He was the highest-ranking US officer to be killed by enemy fire during the entire Second World War. He was replaced by Major General Roy Geiger, who became the only US Marine to command a numbered Army in combat. Geiger was relieved five days later by General Joseph Stilwell.

  The day after Buckner died, Brigadier General Claudius Miller Easley, commander of the 96th Infantry Division, was killed by Japanese machine-gun fire, also while checking on his troops at the front. War correspondent Ernie Pyle had already died the same way, struck by machine-gun fire on Ie Shima on the 18th of April.

  Ushijima and his chief of staff, Lieutenant General Isamu Cho, committed suicide by seppuku in their command headquarters on Hill 89 in the battle's closing hours. Colonel Yahara had asked for permission to do the same. Ushijima refused him, saying: "If you die there will be no one left who knows the truth about the battle of Okinawa. Bear the temporary shame but endure it. This is an order from your army commander." Yahara survived, went into hiding as a civilian, was captured by American soldiers in July 1945, and later wrote a book titled The Battle for Okinawa.

• 8. Aftermath

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  On the 22nd of June 1945, the Tenth Army held a flag-raising ceremony to mark the end of organized resistance. The official surrender ceremony was held on the 7th of September, near Kadena Airfield.

  At least 90 percent of the buildings on Okinawa were destroyed. The island's tropical landscape was, as one historian described it, turned into "a vast field of mud, lead, decay and maggots." Countless historical documents, artifacts, and cultural treasures were gone.

  Military historian Hanson W. Baldwin wrote that the battle "dwarfed the Battle of Britain" in scale and ferocity and that never before had the Navy lost so many ships in so short a time, nor had so much American blood been shed in such a small area in such a brief span.

  Some military historians argue the campaign led directly to the decision to use atomic bombs against Japan. Victor Davis Hanson wrote in Ripples of Battle that because the Japanese on Okinawa "were so fierce in their defense, even when cut off and without supplies," American strategists sought an alternative to a ground invasion of the mainland. The atomic bomb presented itself as that alternative.

  After the battle, Okinawa provided the Allies with a fleet anchorage, troop staging areas, and airfields in close proximity to Japan. Kadena Air Base remains the largest US air base in Asia. In 1995, the Okinawa government erected the Cornerstone of Peace memorial at Mabuni, the site of the last fighting, listing every known name of everyone who died in the battle. As of 2024, that monument carries 242,225 names, and new ones are still being added.