by Daniel Wrinn
The Joint Chiefs decided Iwo Jima must be secured with an Allied airfield built there. This would stop Japanese bombing raids and early warning interceptions. The airfield would offer fighter escorts through the treacherous portions of the B-29’s missions and greater payloads at longer ranges. Iwo Jima in Allied hands would also provide emergency airfield support and landing for crippled B-29s returning from Tokyo and protect the Allied flank for the Okinawa invasion. Admiral Chester Nimitz was given three months to seize and develop Iwo Jima: codename Operation Detachment
Iwo Jima translates to “Sulfur Island” in Japanese. An ugly, foul-smelling, barren chunk of volcanic rock and sand—not even ten square miles in size. According to a Japanese Army officer: “an island of sulfur, no sparrow, no swallow, no water.”
Less poetic Marines described Iwo’s resemblance to a pork chop with a 556-foot volcano. Mount Suribachi dominated the southern end of the island and overlooked all potential landing beaches. Iwo rose unevenly over onto the Motoyama Plateau in the north before falling sharply off into the coast and steep cliffs and canyons. The northern terrain was a defender’s dream: an intricate, broken, cave-dotted jungle of stone. Ringed by volcanic steam and a twisted landscape that seemed like a barren moon wilderness. More than one surviving Marine compared the eerie silence to something out of Dante’s Inferno.
Iwo Jima in 1945 had two redeeming characteristics: the military value of its airfields and the psychological status of the island as a historical Japanese possession. The Allies were now within Japan’s Inner Defense Zone. According to a Japanese officer: “Iwo Jima is the doorkeeper to the Imperial capital.”
Even with the slowest aircraft, Tokyo could be reached in three flight hours from the island. In the Iwo Jima battle, 20,000 Allied and Japanese troops would be killed during brutal fighting in the last winter months of 1945.
No one suggested taking Iwo Jima would be easy. Admiral Nimitz assigned this mission to the same team who’d done so well in the earliest amphibious assaults in the Gilberts, Marshalls, and Marianas. Admiral Raymond Spruance would commend the 5th Fleet, Admiral Richmond Kelly Turner would commend the expeditionary forces, and Admiral Harry Hill would command the attack force.
Operation Detachment required unrelenting military pressure on the enemy and an accelerated planning schedule. The Amphibious task force preparing to assault Iwo Jima was getting squeezed on both ends. Admiral Hill desperately needed amphibious ships, shore bombardment vessels, and landing craft that were currently in use by General Douglas MacArthur and his reconquest of the Philippines. Poor weather and stiff enemy resistance combined to delay the completion of that operation.
The Joint Chiefs reluctantly postponed D-Day on Iwo from January 20 to February 19. The new schedule provided no relief for Allied planners. D-Day on Okinawa could be no later than April 1 because of the monsoon season. This tight timeframe held grim implications for the Marine landing force.
General Harry Schmidt would command the V Amphibious Corps in the assault. Schmidt’s landing force consisted of three Marine divisions (3rd, 4th, and 5th). Schmidt would have the honor of commanding the largest US Marine force ever committed into a single battle—a force totaling over 80,000 troops.
Over half of these troops were Marine veterans from earlier fighting in the Pacific. Realistic training had prepared new Marines for the hard fight to come. The Iwo Jima assault force was arguably the most proficient amphibious force the world had yet to see.
Two senior Marines shared the limelight on Iwo Jima, and history has done them both an injustice. General Holland M. Smith, who then commanded the FMF (Fleet Marine Force), was tasked to participate in Operation Detachment as the Expeditionary Troops’ Commanding General. This was an unnecessary billet. Schmidt had the rank, experience, staff, and resources to execute core level responsibility without being second-guessed.
General Smith was an amphibious pioneer and veteran of landings in the Gilberts, Marshalls, and the Marianas. According to him: “My sun had nearly set by then. I think they asked me along in case something happened to Harry Schmidt.” Smith would try to keep out of Schmidt’s way, but his decision to withhold the 3rd Marines (Expeditionary Troops Reserve) remains as controversial as it was in 1945.
General Smith proved himself an asset to the Iwo Jima campaign. He was always a voice in the wilderness in the top-level planning stage. Smith predicted severe casualties unless more effective preliminary naval bombardment was provided. He diverted visiting dignitaries and the press away from Schmidt and always offered a realistic counterpoint to some of the rosier staff estimates. According to Smith: “It’s a tough proposition, that’s why we’re here.”
General Schmidt’s few public statements left him saddled with predicting Iwo Jima would be conquered in ten days. According to post-war accounts, Schmidt resented Smith’s perceived role: “I was the commander of all troops on Iwo Jima at all times. Holland Smith never had an onshore command post, never issued a single order, and never spent a single night ashore. Isn’t it important from a historical standpoint that I commanded the greatest number of Marines ever to be engaged in a single action in the entire history of the Marine Corps?”
General Smith did not disagree with those points. While Smith proved to be useful, Schmidt and his staff should be credited for planning and executing the difficult and bloody Iwo Jima campaign.
The V Amphibious Corps’ conquest of Iwo Jima was even more remarkable due to tough enemy opposition on the island. General Kuribayashi was one of the most fearsome opponents of the war. Kuribayashi was a fifth-generation samurai handpicked by the emperor. The Japanese general combined combat experience with an innovative mind and an iron will.
Although this would be his only struggle against US forces, he learned much about his opponents from earlier service in the US. Kuribayashi appraised with an unblinking eye the results of previous Japanese attempts to repel Allied invasions of Japanese-held garrisons.
Aside from the heroic rhetoric, Kuribayashi saw little value in the defend-at-the-water’s-edge tactics and suicidal banzai attacks that branded Japan’s failures from Tarawa to Tinian. Kuribayashi was a realist. He did not expect much help from Japan’s depleted fleet and air forces. His best chance was to fortify Iwo’s forbidding terrain with an in-depth defense, similar to the defense on Peleliu. Kuribayashi would shun coastal defenses, anti-landing, and banzai tactics. Instead, he’d wage a battle of attrition: a war of patience, nerves, and time. A delay and bleed strategy. Would the Allied forces lose heart and abandon the campaign?
A passive policy this late in the war was radical to senior Japanese Navy and Army leaders. It was counter to the deeply ingrained Bushido samurai code: a warrior code that viewed the defensive as only an unpleasant delay before the glorious offensive could resume—where the enemy would be destroyed by fire and sword. Imperial Headquarters was nervous. There was evidence of a top-level request for guidance in defending against Allied storm landings from Nazi Germany, whose experience trying to defend Normandy at the water’s edge had proven disastrous.
Japanese command was unconvinced. Kuribayashi used his connection to the Emperor to avoid being relieved. But it was not a complete victory—the Navy insisted on building blockhouses and gun casements along the obvious landing beaches. Kuribayashi demanded assistance from the finest mining engineers and fortification specialists in the Empire.
The island favored the defender. Iwo’s volcanic sand mixed with cement produced an exceptional concrete for installations. The soft rock was easy to dig. Over half of the Japanese garrison put their weapons aside and picked up picks and spades. When Allied bombers from the Seventh Air Force began a daily pummeling of the island in early December 1944, Kuribayashi just moved everything underground: weapons, command post, barracks, and aid stations. The engineering achievements he accomplished were extraordinary. Kuribayashi masked gun positions, created interlocking fields of fire, and miles of tunnels linking key defensive positions. Every cave had
multiple outlets and ventilation tubes. One installation inside Mount Suribachi ran seven stories deep. Allied troops rarely encountered a live Japanese on the island until the bitter end.
Allied intelligence, aided by documents captured in Saipan and by an almost daily flow of aerial surveillance, was puzzled by the Japanese garrison’s disappearing act. The photo interpreters, using stereoscopic lenses, listed 775 potential targets, but all were covered, hardened, and masked. Allied planners knew there was no fresh water available on the island. They saw the rainwater cisterns and knew what the average monthly rainfall would deliver. They determined the enemy garrison couldn’t survive under those conditions in numbers greater than 12,000 for long. But Kuribayashi’s force was twice that size. His troops had existed on half rations of water for months before the battle even began.
Unlike the earlier amphibious assaults on Guadalcanal and Tarawa, Allies would not have a strategic surprise on Iwo. Japanese headquarters believed Iwo would be invaded after the loss of the Marianas. Six months before the battle, Kuribayashi wrote to his wife: “the Americans will most definitely invade Iwo Jima—do not look for my return.”
Kuribayashi ruthlessly worked his men to complete the defensive and training preparations by February 11, 1945. The general met his objective. Kuribayashi had a mixed force of recruits and veterans, soldiers and sailors. His artillerymen and mortar crews were the best in the Empire. Still, he trained and disciplined them all. Each fighting position had the commander’s “Courageous Battle Vows” prominently posted above the firing apertures. Troops were cautioned to maintain their position and to take ten Marine lives for each Japanese death.
General Schmidt issued the operational plan on December 23, 1944. This plan wasn’t fancy. Mount Suribachi towered over the potential landing beaches, but the 3,000 yards of black sand along the southeastern coast were more sheltered from the prevailing winds. It was here the V Amphibious Corps would land on D-Day. The 4th Marine Division on the right, the 5th on the left and the 3rd in reserve. The primary objectives were the lower airfield and Suribachi. Then, the assault force would swing into line and attack north shoulder to shoulder.
Anticipating a significant enemy counterattack on the first night, General Holland Smith said: “We welcome their counterattack. That’s generally when we break their back.”
Kuribayashi's Big Mistake
The physical separation of the three Marine divisions from Hawaii to Guam had no apparent adverse effect on their training. The proficiency of small units in combined arms assaults on fortified positions and amphibious landing were where it counted most. Each division was well prepared for the invasion.
The 3rd Marine Division had just completed their part in the liberation of Guam. Their field training often included active combat patrols to root out and destroy stubborn enemy survivors.
On Maui, the 4th Marine Division prepared for their fourth assault landing in thirteen months with quiet confidence. According to Major Fred Karch: “We had a continuity of veterans that was unbeatable.”
The 5th Marine Division prepared for their first combat experience on the big island of Hawaii. The unit’s newness would prove misleading. Over half of the officers and men were veterans, including several former Marine Raiders and Parachutists who’d fought in the Solomons. Colonel Don Robertson took command of the 3rd Battalion, 27th Marine Regiment with less than two weeks before embarkation and immediately ordered them into the field for sustained live-fire exercises. Their confidence and competence impressed and convinced Robertson that these Marines were professionals.
Among the veterans preparing to deploy on Iwo Jima were two Medal of Honor recipients from Guadalcanal. Gunnery Sargent John Basilone and Colonel Robert Galer. The Marine Corps preferred to keep these distinguished veterans in the US for morale (bond raising) purposes, but both men wrangled their way back into the fight. Basilone led a machine gun platoon and Galer led a new radar unit for the Landing Force Air Support. The Guadalcanal veterans were amazed at the abundance of amphibious shipping available for Operation Detachment. Admiral Turner commanded 497 ships (140 of these were configured for amphib operations). This armada was ten times the size of the Guadalcanal task force.
But there were still problems. Many of the ships and crews were so new that each rehearsal featured an embarrassing collision or other accident. New bulldozers (TD-18s) were an inch too wide for the LCMs. Newly modified M4A3 Sherman tanks were so heavy that the LCMs rode with a dangerously low freeboard. The 105mm howitzers overloaded the DUKWs (amphibious trucks) to the point of unseaworthiness. These factors would soon prove treacherous in Iwo Jima’s unpredictable surf.
Still, the massive Allied armada embarked and began the familiar move westward in good shape, well-trained, well-equipped, and thoroughly supported.
General Kuribayashi had benefited from the Allied delays of Operation Detachment due to the Philippines campaign. He felt as ready and prepared as possible. When the Allied armada sailed from the Marianas on February 13, he was warned. He deployed one infantry battalion into the lower airfield and ordered the bulk of his garrison into their assigned fighting holes—to await the inevitable storm.
Two issues divided the Navy/Marine team as D-Day on Iwo approached. The first was Admiral Spruance’s decision to detach Task Force 58 (the fast attack carriers under Admiral Marc Mitscher) to attack strategic targets on Honshu (Main island of Japan) with the simultaneous bombardment of Iwo. Marine officers suspected a Navy/Air Force rivalry at work: Mitscher’s targets were aircraft factories that the B-29s had missed a few days earlier. Mitscher took all eight Marine Corps fighter squadrons assigned to the fast carriers, plus the new fast battleships with their 16-inch guns. While Task Force 58 returned in time to offer fire support on D-Day, they were off again for good, two days later.
There was a continuing argument between senior Navy and Marine officers over the extent of the preliminary naval gunfire. Marines looked at their intelligence reports on Iwo Jima and requested ten days of preparatory fire. The Navy said it did not have the time nor the ammunition to spare; three days would have to suffice. Generals Smith and Schmidt pleaded their case to Admiral Spruance. Their request was denied. Admiral Spruance ruled that three days of preparatory fire along with the daily hammering administered by the Seventh Air Force would be good enough to get the job done.
Lieutenant Colonel Don Weller was the Task Force 51 naval gunfire officer, and no man knew the business more thoroughly than him. Weller had absorbed the Pacific War’s lessons well. Especially the terrible failures at Tarawa. He argued the issue was not the weight of shells and other caliber but rather the time. The destruction of heavily fortified enemy targets took deliberate and pinpoint firing from close range. They had to be assessed and adjusted by aerial observers. His seven hundred plus hard targets would need time to knock out—a lot of time.
Admiral Spruance did not have time to give for strategic, tactical, and logistical reasons. Three days of firing would deliver four times the shells than Tarawa and would be one and a half time as much delivered against the larger Saipan. It would have to do.
Iwo’s notoriously foul weather and strong enemy fortifications dissipated the three-day bombardment. According to General William Rogers: “We got about 13 hours with the fire support during the 34 hours of available daylight.”
General Kuribayashi committed his only known tactical error during this battle. On D minus 2, a force of one-hundred Navy and Marine frogmen approached the eastern beaches. They were escorted by a dozen rocket-firing LCI (Landing Craft Infantry). Kuribayashi believed this was the main assault and authorized the coastal batteries to open fire. This exchange was hot and heavy with the LCIs getting the worst of it, but the US battleships and cruisers hurried to blast the casement guns that were suddenly revealed on Suribachi’s right flank.
That night, seriously concerned about the hundreds of Japanese targets untouched by two days of firing, Admiral Turner authorized a “war council” on his
flagship and junked the original plan. He ordered the gunships to concentrate exclusively on beach areas. This was done with considerable effect on D minus 1 and D-Day morning.
Kuribayashi noted most of the positions the Imperial Navy insisted on building along the beach were destroyed—just as he predicted. But his central defensive force that crisscrossed the Motoyama Plateau remained intact. “I pray for a heroic fight,” Kuribayashi told his staff.
The press briefing held the night before D-Day on Admiral Turner’s flagship was uncommonly somber. General Holland Smith predicted heavy casualties: upwards of 15,000, which shocked everyone. A man clad in khakis without a rank insignia then stood and addressed the room. It was the Secretary of the Navy, James Forrestal: “Iwo Jima, like Tarawa, leaves very little choice. Except to take it by force of arms, by character, and by courage.”
D-Day on Iwo Jima
On D-Day morning, February 19, Iwo’s weather conditions were ideal. At 0645, Admiral Turner signaled: “Land the landing force.”
Shore bombardments had engaged the enemy island at near point-blank range. Battleships and cruisers steamed in as close as 1,500 yards to level their guns against their island targets. Many of these older battleships had performed this dangerous mission in other theaters of the war. The Nevada, raised from the muck and ruin of Pearl Harbor, led the bombardment force. The battleship Arkansas, built in 1912, had joined the armada from the Atlantic where she’d battered German positions at Normandy during the Allied landing on June 6, 1944.
Colonel “Bucky” Buchanan devised a modified form of the “rolling barrage” used by the bombarding gunships against beachfront targets. This concentration of naval gunfire advanced gradually as troops landed. Always 400 yards to the front. Air spotters would regulate the pace. This innovation was appealing to the division commanders who’d served in World War I France. In those days, a rolling barrage was often the only way to break a stalemate.