(March 28, 2025) This week, 80 years ago, American soldiers, sailors, Marines and airmen, supported by the Royal Navy, were assaulting the Japanese island of Okinawa.
The Prefecture of Okinawa lies about 340 miles south of the Japanese home islands. It is therefore perfectly situated as a forward base of operations for the planned invasion of Japan. On April 1, 1945, the Allies mounted the largest amphibious operation of World War II, in the Pacific, to seize Okinawa. It was code named “Operation Iceberg.”
Six divisions of American troops landed on Okinawa, beginning on April 1, 1945, coincidently both April Fool’s Day and Easter Sunday. The invasion consisted of four divisions of the U.S. Tenth Army and two Marine divisions. In all, the invasion force consisted of almost 200,000 men.
They were supported by a huge armada of naval warships. The main task force, under the command of Vice-Adm. Marc A. Mitscher, consisted of 88 ships (including 11 fleet carriers, six light carriers, seven battleships and 18 cruisers); a British fleet consisting of four carriers, two battleships, five cruisers, 14 destroyers and the fleet train; an Amphibious Support Force, which included 22 escort carriers with more than 500 aircraft, and 10 100-man underwater demolition teams, the precursors of the U.S. Navy SEALS.
The land assault forces were transported and landed by 57 attack transport ships and 67 landing ship tanks, an uncounted number of landing craft, supported by a gunfire support group of 10 older battleships, 11 cruisers, and 30 destroyers.
This is only a partial list and does not include cargo ships, oilers, destroyer escorts, submarines, and all of the other various support vessels in an operation of this magnitude. In all the Allied fleet totaled 1,300 ships.
The Japanese defending the islands were the Thirty-Second Army under the command of Lt. Gen. Mitsuru Ushijima, consisting of 77,000 regular army soldiers, 9,000 Imperial Navy sailors, of which only a few hundred had been trained for ground combat, and approximately 39,000 local Okinawans who had been impressed into a rear-guard militia. In addition, the Japanese made use of an incredible number of kamikaze attack aircraft during the battle.
On April 1, 1945, at 05:30, 20 minutes before dawn, the fire support force of 10 battleships, nine cruisers, 23 destroyers, and 177 gunboats began the pre-H-Hour bombardment of the beaches. They fired 44,825 rounds of 5-inch or larger shells, 33,000 rockets, and 22,500 mortar shells. This was the heaviest concentration of naval gunfire ever to support a landing of troops.
About 70 miles east of Okinawa, Task Force 58 was deployed to furnish air support and to intercept attacks from Kyushu. In addition, support carriers had arrived with troop convoys. At 7:45, carrier planes struck the beaches and nearby trenches with napalm.
Within an hour of the initial landings, 16,000 troops were ashore. They were followed by hundreds of tanks. The landings were, mostly without resistance which, at the time, seemed ominous. An infantryman of the 7th Division, standing atop a hill just south of the Bishi River, soon after the landing, expressed the common feeling when he said, “I’ve already lived longer than I thought I would.”
By nightfall the beachhead was 15,000 yards long and in places as much as 5,000 yards deep. More than 60,000 men were ashore, including the reserve regiments of the assault divisions. Kadena and Yontan airfields, each about a mile inland were easily captured on the first day of fighting. A few Japanese aircraft rose to contest the landings and a few shells were fired but the resistance was mostly ineffectual. This would not last.
After approximately one week of relatively light fighting, the real battle began. On April 6, 400 Japanese aircraft attacked the Allied fleet and land positions. Numerous kamikaze attacks also damaged Allied ships.
In one of the strangest military operations in history, the mammoth Japanese battleship, Yamato, left the Japanese home islands and, along with escorting vessels steamed for Okinawa. The plan was for the Yamato to beach itself on Okinawa and then use its formidable 18-inch guns as fixed land-based artillery.
She and her sister ship, Musashi, were the heaviest and most powerfully armed battleships ever constructed, displacing 72,800 tons at full load and armed with nine 18.1-inch, 45 caliber Type 94 main guns, as opposed to the Bismarck which carried 15-inch guns or, the Iowa class battleships which carried 16-inch guns.
An American submarine, lying off Kyushu, reported the movement of the Japanese warships, and 40 planes of Task Force 58 began a far-flung search, at dawn, on April 7. At 8:22 a plane from the Essex sighted the enemy force, which consisted of the battleship Yamato, the light cruiser Yahagi, and eight destroyers, in the East China Sea, on a course toward Okinawa.
Task Force 58, which had started northeastward at 4 that morning in order to close with the enemy, launched its planes at a point estimated to be 240 miles from the enemy fleet.
The first attacks, through heavy, but inaccurate, antiaircraft fire, scored at least eight torpedo and five bomb hits on the Yamato, the Yahagi, and three of the destroyers. Subsequent attacks succeeded in sinking the Yamato, the Yahagi, and four destroyers; one destroyer was seriously damaged and one left burning. Task Force 58 lost only 10 planes out of the 386 that participated. Okinawa was now safe from surface attack.
The total Japanese air effort was far greater than that encountered in any other Pacific operation. The proximity of airfields in Kyushu and Formosa permitted the deployment by the enemy of all types of planes and pilots.
Together, there were 896 air raids against Okinawa. Approximately 4,000 Japanese planes were destroyed in combat, 1,900 of which were suicide planes. The intensity and scale of the Japanese suicide air attacks on naval forces and shipping were the most spectacular aspects of the Okinawa campaign.
Between 6 April and 22 June there were 10 organized kamikaze attacks, employing a total of 1,465 planes. In addition, sporadic small-scale suicide attacks were directed against the American fleet by both Army and Navy planes, bringing the total number of suicide sorties during the campaign to 1,900.
The violence of the air attacks is indicated by the damage inflicted on the American forces. Twenty-eight ships were sunk and 225 damaged by Japanese air action during the campaign. Destroyers sustained more hits than any other class of ships. Battleships, cruisers, and carriers also were among those struck.
Some of the big naval ships suffered heavy damage with great loss of life. The radar picket ships, made up principally of destroyers and destroyer escorts, suffered proportionately greater losses than any other part of the fleet. The great majority of ships sunk or damaged were victims of the kamikaze. Suicide planes accounted for 26 of the 28 vessels sunk and for 164 of the 225 damaged by air attack during the entire campaign.
The land battle for Okinawa lasted 82 days, from April 1 to mid-June 1945.
The battle was one of the bloodiest in the Pacific — especially for civilians. Based on Okinawan government sources, 42,000–150,000 local civilians were killed or committed suicide, a significant proportion of the local population. One of the most controversial scenes during the Second World War was Okinawan civilians, some holding their children, jumping from cliffs to their deaths due to warnings from the Japanese Army that they would be raped and murdered by the Americans.
The main strategy, of the Japanese forces on Okinawa, was to fight a defensive battle, bleeding the invaders as much as possible and never surrendering. This, then, involved a long, costly slog the length of the islands against dug-in fanatical troops. One such operation involved the Shuri Defense line of April 29.
As the morning mists cleared, the campaign’s largest single air strike was delivered. By 9 a.m. Yonabaru had been hit by 67 planes spreading napalm that burned everything above ground. Iwa had been devastated by a strike of 108 planes, and Shuri by a strike of 139.
A total of 650 Navy and Marine planes bombed, rocketed, napalmed, and machine-gunned the enemy. Six battleships, six cruisers, and six destroyers of the Fifth Fleet added their fire power to that of the planes and artillery. These sledgehammer blows fell on about 4,000 combat veterans of the Japanese 62d Division who were manning the positions.
The greatest concentration of artillery ever employed in the Pacific war sounded the prelude to the attack at dawn. Twenty-seven battalions of corps and division artillery — 324 pieces in all — ranging from 105-mm to 8-inch howitzers, fired the first rounds at 6 a.m.
This concentration represented an average of 75 artillery pieces to every mile of front, and actually it was even greater as the firing progressed in mass from east to west. The shells thundered against the enemy’s front lines for twenty minutes, then shifted 500 yards to the rear, while the infantry simulated a movement as if beginning the attack. At 6:30 a.m., the artillery shifted back to spray the enemy’s front lines for the next ten minutes with time fire. In forty minutes American artillery placed 19,000 shells on the enemy’s lines. Then, at 6:40 a.m., the artillery lifted to enemy rear areas.
The assault platoons advanced, hopeful that the great mass of metal and explosives had destroyed the enemy, or had left him so stunned that he would be helpless. They were soon disillusioned, for the Japanese, deep in their caves, had scarcely been touched, and at the right moment they manned their battle stations.
Brig. Gen. Josef R. Sheetz, commanding general, XXIV Corps Artillery, later said he doubted that as many as 190 Japanese, or one for every 100 shells, had been killed by the morning artillery preparation.
Until American troops occupied the last of its defensive terrain, the Japanese Army, in spite of adversities and broken fortunes, had maintained discipline and organization astonishingly well. When the process of dissolution began, however, it spread like an epidemic. Most Japanese soldiers lost hope of eventual victory when they abandoned Shuri.
Mass surrender of Japanese soldiers did not begin until the Tenth Army crowded them almost to the water’s edge. There was a noticeable increase, however, after the intensification of the psychological warfare program.
During the first 70 days of battle, prisoners captured by Tenth Army averaged less than four a day. This average increased to more than 50 a day between June 12 and 19; and on June 19, as the 6th Marine and 7th Infantry Divisions rolled forward near the east and west coasts, 343 enemy soldiers voluntarily surrendered.
On the afternoon of June 20, the 32nd Infantry seized the east end of Hill 89, a coral bulge next to the sea that housed Gen. Ushijima’s staff and headquarters. On the same day 977 prisoners were taken — an unprecedented accomplishment in the Pacific war.
On June 22, 1945, with their backs to the sea Gen.Ushijima and his chief of staff, Gen. Isamu Chõ, committed suicide. This effectively ended resistance on Okinawa.
The price paid for Okinawa was dear. The final toll of American casualties was the highest experienced in any campaign against the Japanese. Total American battle casualties were 49,151, of which 12,520 were killed or missing and 36,631 wounded.
Army losses were 4,582 killed, 93 missing, and 18,000 wounded; Marine losses, including those of the Tactical Air Force, were 2,938 killed and missing and 13,708 wounded; Navy casualties totaled 4,907 killed and missing and 4,824 wounded.
Non-battle casualties during the campaign amounted to 15,613 for the Army and 10,598 for the Marines. The losses in ships were 36 sunk and 368 damaged, most of them as a result of air action. Losses in the air were 763 planes from 1 April to 1 July.
In addition, just four days from the closing of the campaign, Lt. Gen. Simon Bolivar Buckner, the commander of the ground forces, was killed by Japanese artillery fire, which blew lethal slivers of coral into his body. He was the highest-ranking U.S. officer to be killed by enemy fire during the war. The famous war correspondent Ernie Pyle was also killed during the battle.
The high cost of the victory was because the battle had been fought against a capably led Japanese army of greater strength than anticipated, over difficult terrain heavily and expertly fortified, and thousands of miles from home. The campaign had lasted considerably longer than was expected. But Americans had demonstrated, again on Okinawa, that they could, ultimately, wrest from the Japanese whatever ground they wanted.
The cost of the battle to the Japanese was even higher than to the Americans. Approximately 110,000 of the enemy lost their lives in the attempt to hold Okinawa, and 7,400 more were taken prisoners.
The enemy lost 7,800 airplanes, 16 ships sunk, and four ships damaged. More important, the Japanese lost 640 square miles of territory within 350 miles of Kyushu.
The American forces then began feverish preparations for the invasion of Japan, but on Aug.6, 1945, the atomic bomb was dropped on Hiroshima, followed two days later by a second atomic bomb on Nagasaki. The war was over. The battle of Okinawa was the last battle of World War II for the Americans.
Acknowledgements: Thanks to “Okinawa: The Last Battle” by Roy E. Appleman, James M. Burns; Russell A. Gugeler, and John Stevens, Center of Military History, United States Army, Washington, D. C., (1948)
Next week: Red Army Captures Bratislava
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