By Col Joseph H. Alexander, USMC (Ret) - Originally Published April 2005
For the Marines and soldiers of the U.S. Tenth Army, the three-month battle for Okinawa was both a pinnacle of amphibious skill and a preview of even bloodier landings ahead in the scheduled invasion of the Japanese home islands.
The fighting on Okinawa reflected the accelerating pace and increased lethality of the Pacific campaigns as the fourth year of the war began. The U.S. Marines, having fielded an unprecedented six divisions by that time, fought the two largest battles in their history within a four-month span. Less than a week after three Marine divisions completed the capture of I wo Jima, the other three divisions assaulted Okinawa.
Victories in both campaigns cost the Marines (and their organic Navy corpsmen) a combined total of 44,000 combat casualties-the equivalent of losing two entire divisions. More than 9,700 Marines and Navy corpsmen and surgeons died in the two battles, representing half of all combat deaths sustained by the Corps in the Pacific war. No one doubted that the butcher's bill for Operation Downfall, the planned invasion of Japan, would cost even more.
Iwo Jima remains a special touchstone to Marines, but Okinawa had its own horrors and heroes. The two campaigns differed markedly. Okinawa, a much larger island than Iwo Jima, lay 300 miles closer to Japan's home airfields. The fighting on Iwo Jima lasted five weeks, while that on Okinawa lasted 11. The fighting on Iwo Jima took place in the total absence of civilianssimilar to Tarawa and Peleliu earlierbut the Marines on Okinawa fought amid nearly a half-million native Ryukyuans, a third of whom died during the campaign.
Japan's extended use of suicide tactics made the critical difference in the two battles. Japanese suicide planes (kamikazes) attacked the U.S. 5th Fleet only once at Iwo Jima, sinking a carrier and crippling another. At Okinawa the Japanese unleashed several thousand kamikazes that ravaged the fleet day and night, week after week, sinking 38 ships and damaging 368 more, the worst losses ever experienced by the U.S. Navy. This wholesale employment of suicide attackers by the Japanese cast the most chilling preview of Operation Downfall.
Defending Okinawa in 1945 became the responsibility of lieutenant General Mitsuru Ushijima and his 32nd Army, a force of more than 100,000 soldiers, augmented by heavy artillery units. A coral reef surrounded the island. The Japanese enhanced this barrier with antiboat mines and rows of sharpened wooden stakes, then commenced to fortify the lower half of the skinny, 60-mile-long island.
Fleet Admiral Chester W. Nimitz, commanding the Central Pacific theater, retained his proven "first team" to lead the assault on Okinawa. ADM Raymond A. Spruance commanded the U.S. 5th Fleet; Vice Admiral Marc A. Mitscher, the fast carriers; and VADM Kelly Turner, the amphibious forces. The three veterans had worked seamlessly together at Kwajalein, Saipan and Iwo Jima.
Army Lieutenant General Simon Bolivar Buckner Jr., the son of a Confederate general, commanded the 162,000 Marines and soldiers of the U.S. Tenth Army. LTG Buckner's troops held a detided edge in combat experience over LtGen Ushijima's 32nd Army. The ranks of the First, Second and Sixth Marine divisions contained men who had fought throughout the Solomons and the Central Pacific. Many soldiers of the 7th, 27th, 77th and 96th divisions had fought in the Aleutians, Central Pacific and the Philippines. Very few Japanese survived those campaigns to fight again on Okinawa. One who did was Rear Admiral Minoru Ota, who had commanded the Japanese special naval landing forces in the repulse of the 2d Raider Regiment's attack on Bairoko in New Georgia in 1943.
Major General Roy S. Geiger, commanding the III Amphibious Corps, had become a leatherneck legend before most of his Marines had been born. Decades earlier he walked away from his civilian profession as an attorney, enlisted in the Marines as a rifleman, earned a commission, led an infantry platoon in combat in Nicaragua, and became one of the earliest pioneers of Marine aviation. In the Pacific war, Maj Gen Geiger commanded the storied Cactus Air Force at Guadalcanal and then commanded an amphibious corps for the Bougainville, Guam and Peleliu landings.
MajGen Pedro A. del Valle, formerly the artillery commander at Guadalcanal, commanded the 1 stMarDiv, whose most recent fight was Peleliu. MajGen Lemuel C. Shepherd Jr., the future Commandant, led the newly created 6thMarDiv, brimming with veterans, including former Raiders. MajGen Francis P. Mulcahy, one of the few Marine aviators to shoot down a German fighter in World War I, commanded the Tenth Army's Tactical Air Force and the second Marine Aircraft Wing.
Key U.S. Army attachments supported MajGen Geiger's Marine divisions, including the 713th Armored Flame Thrower Battalion and the 88th Chemical Mortar Bn, a 4.2-inch mortar outfit that protected each attack and withdrawal with smoke munitions. MajGen Geiger would need the most from every element of this joint team to prevail against the defenses of the Japanese 32nd Army.
The strength of the Japanese defenders on Okinawa lay in their uncanny ability to dig defensive fortifications with scant tools and little time. Most Americans assumed after the battle that the Japanese had taken years to prepare the network of mutually supporting caves, tunnels, bunkers and reverse slope positions in the southern half of the island. Actually, LtGen Ushijima's men commenced the bulk of this labor barely four months before the American invasion. At ancient Shuri Castle, crowning a ridge in the island's center, the soldiers carved out hundreds of feet of subterranean positions and tied in the high citadel with complex strongpoints on both flanks at Sugar Loaf Hill and Conical Hill. In the end, the Yonabaru-Shuri-Naha Line became one of the strongest defensive strongholds the United States ever faced in the Pacific war.
Four days before the landing, VADM Mitscher advised LTG Buckner that his aviators found southern Okinawa to be "honey-combed with caves, tunnels and emplacements." VADM Mitscher predicted a very tough job ahead for the Tenth Army.
Imperial General Headquarters (IGHQ) encouraged LtGen Ushijima to lie low and allow the massed kamikazes and hidden suicide powerboats to disrupt the U.S. landing. Should the Americans somehow straggle ashore in force, IGHQ expected LtGen Ushijima to utilize his fortified defenses to wage a protracted battle of attrition.
Anticipating the usual Japanese defense at the water's edge, the 5th Fleet wasted several days of preliminary bombardment of the area inshore from the designated beaches near Hagushi on the west-central coast, expending shells that in hindsight could have been used more effectively in Iwo Jima's abbreviated bombardment. Japanese staff officers watched the shelling from the safety of their bunkers along the Shun Line, eight miles south, and congratulated themselves on their deception.
The 5th Fleet landed four divisions on line along the Hagushi beaches on 1 April 1945 in what was thus a spectacular but anticlimactic assault. Sixty thousand Marines and soldiers poured ashore the first day, a complex ship-to-shore movement executed to perfection. Some Marineswarned the previous night to expect 75 percent casualties in the assault-rode ashore in their amphibian tractors singing at the tops of their lungs in relief. It was Easter Sunday.
Japanese plans for thwarting the landing with suicide forces failed. VADM Turner's advance seizure of the nearby Kerama Retto Islands for a fleet harbor resulted in the unexpected and fortunate capture of most of LtGen Ushijima's fleet of 350 powerboats, packed with explosives and meant for ramming the U.S. transports at high speed. Nor could kamikaze attacks deter the landing, despite hitting ADM Spruance's flagship the previous day. ADM Spruance smothered likely kamikaze fields throughout a 700-mile arc around Okinawa with every plane he could launch, and the fleet shielded the vulnerable transports all the way to the line of departure. No loaded troop transports took casualties that day, an achievement of astounding proportions considering the ship losses that ensued throughout the following weeks.
Life ashore was initially benign for the Tenth Army. Soldiers of the XXIV Corps cut the island in half, the 6thMarDiv rolled north in a high-mobility pursuit of an enemy brigade, and the 77th Infantry Div captured the offshore island of Ie Shima. Then the XXIV Corps encountered the outer defenses of the Shun Line, and reality set in.
Breaching the Shuri defenses proved incredibly difficult, in spite of the Tenth Army's firepower and collective combat experience. LTG Buckner initially deployed two Army divisions abreast, then ordered MajGen Geiger's two Marine divisions into line. (The 2dMarDiv, LTG Buckner's reserve, had returned to Saipan on call after executing a diversionary landing on the opposite coast.) Four divisions fighting abreast along a line less than five miles long left little room for independent maneuver, and the Tenth Army's rate of advance slowed to a few hundred yards a day. All too quickly the struggle for Okinawa became a slogging, bloody war of attrition-exactly what LtGen Ushijima wanted.
The Marines fought and bled over rocky ridges and escarpments with names that became achingly familiar: the Awachi Pocket, Dakeshi Ridge, Wana Draw, Sugar Loaf Hill and its over-watching outposts on Half Moon Hill, Horseshoe Hill and Kunishi Ridge, the final heartbreaker that chewed up so many rifle companies at the end of the campaign.
The Tenth Army's slow advance against the Shuri Line left the 5th Fleet increasingly vulnerable to kamikaze attacks as it clustered offshore in support of the ground campaign with naval gunfire, air strikes and supplies. The Japanese may have missed a golden opportunity to strike the troop transports before the landing, but by concentrating their subsequent air attacks against the fleet, Imperial Headquarters seemed to have finally devised a strategy capable of derailing an amphibious campaign.
The 5th Fleet fought back furiously. Shipboard antiaircraft gunners combined with MajGen Mulcahy's Marine combat air patrols to knock down four of every five kamikazes that approached, but the survivors did great damage to the ships. In concern, ADM Nimitz flew to Okinawa and urged LTG Buckner to expedite the fighting ashore. LTG Buckner replied that only more firepower could provide the breakthrough.
The stalemate's solution seemed evident to several of LTG Buckner's subordinates. MG Andrew D. Bruce of the 77th Infantry Div, whose amphibious credentials included Guam, Ormoc, Kerama Retto and Ie Shima, recommended a seagoing left hook, a division landing at Minatoga, seven miles southeast of the Shuri Line. So did MajGen Shepherd, who suggested LTG Buckner give the mission to the 2dMarDiv, the Tenth Army reserve now ashore in Saipan, but with its ships nearby and still combat-loaded.
"I felt very strongly," said MajGen Shepherd, "that if the second Division was landed in the rear of the Japanese lines, even if it only established and defended a beachhead line, it would require the Japanese to contain it, thereby weakening their main defense line which the remainder of the Tenth Army was having such a difficult time penetrating."
LTG Buckner balked. He was already experiencing severe logistic support problems, and he doubted his ability to resupply and if necessary reinforce or evacuate an isolated division from the sea. He refused to consider an amphibious flank attack.
Many Marines, then and now. have agreed with MajGen Shepherd's conclusion that LTG Buckner, "like so many Army officers, did not cotton to amphibious operations." Some have suggested LTG Buckner could have taken a page from the successful flanking tactics of Ulysses S. Grant, the Union general who captured LTG Buckner's father and his forces at Fort Donelson in the Civil War. Others have implied that LTG Buckner wanted to avoid giving the Marines more public exposure as the potential saviors of a bloody, bogged-down campaign.
Yet the issues and motives in April-May 1945 on Okinawa were more complex. LTG Buckner was neither unfamiliar with nor opposed to amphibious operations. He had participated in the 7th Infantry Div's landings in the Aleutians in 1943 and had studied the U.S. Army's disastrous amphibious flank attack at Anzio, Italy, in early 1944.
Under LTG Buckner's command the Tenth Army had just executed the massive landings on 1 April that proved to be as close to perfect as any other major assault in the Pacific. The assault from the sea had included many features not affordable at Tarawa, including extensive advance force operations, seizure of offshore islands as fleet harbors and fire support bases by Marine amphibious reconnaissance troops and Army regimental combat teams, and a highly sophisticated and successful amphibious feint at Minatoga by the 2dMarDiv.
Nor was LTG Buckner opposed to the Marine Corps. He had 34 Marines on his staff, including the highly regarded Brigadier General Oliver P. Smith as deputy chief of staff, and he listened to their ideas. He personally arranged for MajGen Geiger to assume command of the Tenth Army in the event of his death (as the case proved to be), despite strong opposition from the Commanding General, U.S. Army Pacific.
Okinawa was LTG Buckner's first combat command, and if he lacked the aggressiveness of "Howlin' Mad" Smith or the audacity of Ulysses Grant, he proved to be competent and personally brave under fire. The postwar debate about the merits of an amphibious "left hook" at Okinawa continues, but in the spring of 1945 LTG Buckner believed a Minatoga landing could fail spectacularly, eliminate his reserve and jeopardize the campaign. LTG Buckner believed his best option against the Shuri defenses was to keep driving straight ahead.
A grim month passed, and when U.S. troops finally swarmed over Shuri Castle, LtGen Ushijima artfully retreated to another line of prepared defenses in the south. The Japanese, as it turned out, had worried considerably about an amphibious assault on Minatoga. LtGen Ushijima's captured operations officer, lieutenant Colonel Hiromichi Yahara, admitted under interrogation that "the absence of a landing [at Minatoga] puzzled the 32nd Army staff, particularly after the beginning of May when it became impossible to put up more than a token resistance in the south."
Weeks later, MajGens Geiger and Shepherd beseeched LTG Buckner to authorize a shore-to-shore amphibious assault by the 6thMarDiv against the Oroku Peninsula below Naha on the West Coast. LTG Buckner agreed. Hurriedly executed to beat a looming typhoon, MajGen Shepherd's waterborne flank attack caught RADM Ota's 5,000-man naval guard force by surprise. RADM Ota fought fiercely, inflicting stiff casualties on the Marines and their tanks, but after 10 days he acknowledged defeat and committed suicide.
Elsewhere, LTG Buckner's grinding frontal assaults continued inexorably. Persistent rains turned the battlefield into a sea of mud. Private Eugene B. Sledge of the Fifth Marine Regiment recalled the misery of the fighting east of Sugar Loaf Hill. "The heavy rains started the day after we moved up onto Half Moon Hill," he said. "I was appalled at the number of Marine dead in the area. The odor was as bad or worse than Peleliu."
The campaign took a heavy toll among key Marine leaders. Of the 18 infantry battalion commanders who landed with the 1st and 6thMarDivs, four were killed and nine badly wounded during the fighting. Corporal James L. Day, a squad leader in the 22d Marines, who was belatedly awarded a Medal of Honor in 1998 for his valor on Sugar Loaf Hill, was wounded twice during the campaign and also experienced the death of his regimental and battalion commanders and the loss of two company commanders, seven platoon commanders and every member of his rifle squad.
If there was a redeeming grace for the Marines in the campaign, it was the experience of teaming at last with Marine aviation. At Okinawa-more so than any earlier campaign-Marine air fought the same enemy at the same time as the ground troops. Yet it involved a strange juxtaposition. Each dawn Marine pilots would take off from captured airfields on Okinawa to fly combat air patrols in protection of the 5th Fleet, passing inbound Navy squadrons launched from carriers to fly direct support missions for the infantry. Marine pilots actually flew a variety of missions, including classic close air support for the Tenth Army as well as emergency parachute drops of much-needed food for the Marines, whose logistic support systems were not as effective in such a protracted campaign as the Army's.
Japanese artillery fire killed LTG Buckner on 18 June while he observed the Marines attacking in the south. As arranged, Maj Gen Geiger replaced him in command of the Tenth Army, becoming the first Marine and the only aviator of any service to command a field army. Three days later, following the death of LtGen Ushijima, MajGen Geiger declared the end of organized resistance on Okinawa. Two days later MajGen Geiger relinquished command to Army GEN Joseph "Vinegar Joe" Stillwell.
Seizing Okinawa cost the Tenth Army nearly 40,000 casualties. Total Marine Corps combat losses-ground, air and ships' detachments-amounted to more than 19,500 men.
There was scant celebration by the Marines as the fighting ceased. Many were beset with survivor's guilt; most were already fatalistic about the landings to come. Operation Downfall envisioned two enormous landings in the Japanese homeland, the first on Kyushu with 14 divisions on 1 Nov. 1945, and the second on the main island of Honshu, near Tokyo, with 25 divisions, scheduled for 1 March 1946. All six Marine divisions and three of the four existing Marine aircraft wings would play key roles.
The prospects were grim. Planners spoke of even greater swarms of kamikazes and more effective suicide powerboats, plus a civilian population motivated to fight to the death alongside the Imperial troops. Home seemed very far off. "The Golden Gate in '48" was an ironic slogan in the ranks.
The successive U.S. victories at Iwo Jima and Okinawa demonstrated that America possessed the will and the wherewithal to prevail in large-scale, forcible, amphibious assaults, despite the furies of hell. Although Operation Downfall would have incurred frightful costs to both sides, Japan's ultimate defeat was assured. Yet it was the prospect of these combined civilian-military casualties that helped convince President Harry S. Truman and the Joint Chiefs of Staff that the atomic bomb represented the lesser and more humane of two evils. The bombs fell on Hiroshima and Nagasaki six weeks after the battle for Okinawa. The Emperor surrendered, the Americans canceled their planned invasions, and most of the troops in the Western Pacific got to glimpse the Golden Gate a lot sooner than they ever dreamed.
Editor's note: Col Alexander, noted author and military historian, served 29 years on active duty as an assault amphibian officer, including two tours in Vietnam. He has commenced his fourth year as chief historian of the exhibit design team for the National Museum of the Marine Corps.
Col Alexander has published five books, including "The Battle History of the Marine Corps," "Utmost Savagery" and Storm Landings," and has appeared in 25 documentaries for The History Channel, A&E Network and FOX News Channel. He is a frequent contributor to Leatherneck.