by Daniel Wrinn
Marine Corps Headquarters backed up these last-minute changes by providing the required replacements to land the assault divisions at full strength. Sometimes the skills required did not match. Some artillery regiments absorbed a flood of radar technicians and anti-aircraft artillery gunners from old defense battalions. But the manpower and equipment shortfalls that had plagued earlier operations were overcome by the time the assault force embarked on Operation Iceberg.
Even this late in the war, operational intelligence was unsatisfactory before the landing. At Tarawa and Tinian, the pre-assault combat intelligence had been brilliant. But at Okinawa, the landing force did not have accurate figures of the enemy’s weapons or abilities.
The cloud cover over the island prevented accurate and complete photo-reconnaissance. Also, the ingenuity of the Japanese commander and the extraordinary digging skills of the enemy garrison helped disguise the island’s true defenses.
Japanese Defenses
Okinawa is sixty miles long, but only the lower third of the island had the military objectives of anchorages, ports, and airfields. In August 1944. Japanese General Mitsuru Ushijima took command of the Thirty-second Army. He understood the fight would be fought in the south and concentrated his forces there.
He decided to not challenge the probable Allied landings in Hagushi along the broad beaches of the southwest coast. He believed that doing so would lose him the Kadena and Yontan Airfields. This decision allowed him to conserve his forces and fight the only battle that stood a chance: an in-depth defense, underground and protected from the overpowering Allied air and arms superiority.
This clash of cave warfare and attrition would be like the recent battles on Peleliu and Iwo Jima. Each had taken a terrifying cost to Allied invaders. General Ushijima sought to replicate this strategy. He would go underground and sting the Allies with high caliber gunfire from his freshly excavated fire-port caves. He believed by bleeding the landing force and bogging down their momentum, he could buy the Imperial Army and Navy’s air arms enough time to destroy the fifth fleet with massed kamikaze attacks.
General Ushijima had 100,000 Imperial troops on the island, including thousands of Okinawan Home Guard (conscripts known as Boeitai). He had a disproportionate number of heavy weapons and artillery in his command. The Allies in the Pacific would not encounter a more formidable concentration of 47mm antitank guns, 320mm spigot mortars, 120mm mortars, and 150mm howitzers. The strategic decision to invade Peleliu, Iwo Jima, and the Philippines before Okinawa gave the enemy seven months to develop their defenses.
Allied forces had already seen what the Japanese could do to fortify a position in a short time. On Okinawa they achieved stunning success. They worked almost exclusively with hand tools: not one bulldozer on the entire island. The Japanese dug miles of underground fighting positions and honeycombed southern Okinawa’s ridges and draws. They stocked each position with reserves of food, water, ammunition, and medical supplies. Allied forces anticipated a fierce defense of the southwestern beaches and the airfields, followed by a general counterattack. Then, the battle would be over except for some mop-up and light patrolling.
The Allies could not have been more mistaken.
The assault plan called for the advance seizure of the Kerama Retto Islands after several days of preparatory air and naval bombardment. Followed by a massive four-division assault on the Hagushi Beaches. During the primary assault, the 2nd Marine Division, with a separate naval task force, would duplicate the assault on Okinawa’s southeast coast (Minatoga Beaches).
Love-Day (chosen to avoid planning confusion with D-Day being planned for Iwo Jima) would happen on April 1, 1945. Hardly anyone failed to remark about the irony of April Fool’s Day and Easter Sunday.
The US Fifth Fleet was a breathtaking sight as it steamed toward the Ryukyus. Marines who’d returned to the Pacific from the original amphibious offensive on Guadalcanal thirty-one months earlier gaped at the quantity of landing craft in the assault ships. The armada stretched to the horizon—a genuinely incredible, mind-boggling vista.
On March 26, the 77th Infantry Division skillfully secured Kerama Retto. A move that surprised the Japanese and generated enormous operational dividends. Admiral Turner now had a series of sheltered anchorages to repair ships likely to be damaged by kamikaze attacks. Soldiers discovered stockpiled Japanese suicide boats—over 300 powerboats equipped with high explosive rams to sink the thin-skinned troop transports.
Major James Jones commanded the Force Reconnaissance Battalion. His battalion paved the way before each landing with stealthy scouting missions the night before. Jones’ recon Marines scouted and found the barren sand spits of Keise Shima undefended. After reporting that welcome news, the Army landed a battery of 155mm “Long Toms” on the small inlets, adding to their significant firepower and the naval bombardment of Okinawa’s southwest coast.
Admiral Turner’s minesweepers cleared approaches to the southwestern beaches. Navy frogmen and Marines detonated hundreds of man-made obstacles. After seven days of preliminary bombardment, Allied ships fired over 25,000 rounds of 5-inch shells. This shelling produced more of a spectacle than a destructive effect. The Allied forces believed General Ushijima’s troops would be arrayed around the beaches and airfields. While that scale and duration of bombardment would’ve saved many lives on Iwo Jima: on Okinawa, this precious ordinance was largely wasted and produced few results.
Tensions were high in landing force transports. The 60mm mortar section of Company K, 3/5 Marines learned that the casualty rates on Love-Day were estimated to reach 85%. According to Private First Class Eugene Sledge: “this is not conducive to a good night’s sleep.”
A Japanese soldier observing the massive armada bearing down on Okinawa wrote in his diary: “it’s like a frog meeting a snake and waiting for the snake to eat him.”
Land the Landing Force
The Allied invasion got off to a roaring start. The few enemy defenders still in the area at dawn on April 1 immediately agreed with the wisdom of conceding the beaches to the landing force.
The massive armada gathered from ports all over the Pacific now bore down on Okinawa’s southwest coast: ready to deploy a 182,000-man landing force onto the beach. The ultimate forcible entry—the embodiment of all painfully learned amphibious lessons from the crude beginnings at Guadalcanal and North Africa.
Admiral Turner made his final review of the weather conditions in the objective area. As at Iwo Jima, the amphibious assault was fortunate to have good weather for the critical initial landing. Skies were clear, winds and surf were moderate. The temperature was 75 degrees.
At 0406, Turner ordered: “Land the landing force.” That phrase set off a sequential countdown to the first assault waves smashing into the beaches at H-hour. Combat troops crowded the rails of the transports to witness an extraordinary display of Allied naval power. A sustained bombardment by rockets and shells from hundreds of ships. Formations of Allied attack aircraft streaked low over the beaches: strafing and bombing at will. Japanese fire was ineffective and scattered, even against this massive armada assembled offshore.
The diversionary force carrying the 2nd Marine Division set out to bait the Japanese with a feint landing on the opposite coast. This amphibious force steamed into position and launched amphibian tractors and Higgins boats loaded with combat Marines in seven waves toward Minatoga Beach. The fourth wave commander paid careful attention to the clock and crossed the line of departure at exactly 0830—the time of the actual H-hour assault on the western coast. Then, the Higgins boats and LVTs turned away and returned to the transports: mission accomplished.
The diversionary landing achieved its purpose. General Ushijima had placed several front-line infantry and artillery units in the Minatoga Beach area for several weeks as a contingency against an expected secondary landing. His officers reported to Imperial headquarters on Love-Day morning: “enemy landing attempt on east coast blocked with heavy enemy losses.”
; This deception came at a high cost. Kamikaze pilots were convinced this was the main assault. They came in waves and struck the small force that morning, damaging the troopships LST 844 and Hinsdale. The 3/2 Marines and the 2nd Amphibian Tractor Battalion suffered fifty casualties. The troopships lost an equal number of sailors. Ironically, the division that was expected to have the most minor damage or casualties in the battle lost more men than any other division in the Tenth Army that day. According to Operation Officer Colonel Sam Taxis: “we’d requested air cover for the feint but were told the threat was ‘incidental.’”
In the southwest, the main assault force faced little resistance. A massive coral reef provided an offshore barrier to the beaches on Hagushi. But by early evening, the reef no longer presented a threat to the landing force. Unlike on Tarawa, where the reef dominated the tactical progress of the battle. General Buckner had over 1,400 LVTs to transport the assault waves from ship to shore without delay.
Eight miles of LVTs churned across the line of departure just behind 360 armored LVT-As that blasted away at the beach with their snub-nosed 75mm howitzers as they advanced the final four thousand yards. Behind the LVTs were 750 amphibious trucks with the first of the direct support artillery battalions. The horizon behind the amphibious trucks was filled with lines of landing boats. They paused at the reef to marry with the outbound LVTs. Marines and soldiers had exhaustively rehearsed transfer line operations—there was no pause in the assault momentum.
The Bisha Gawa river mouth marked the boundary between IIIAC and XXIV Corps along the Hagushi beaches. The tactical plan called for the two divisions to land abreast—the 6th on the left and the 1st on the right. The endless rehearsal of thousands of hours paid off. The initial assault touched down at 0830: the designated H-hour. Marines stormed out of their LVTs, swarming over the sea walls and berms into the great unknown. The Okinawa invasion had begun. Within the first hour, the Tenth Army had over 16,000 combat troops ashore.
Despite the dire intelligent predictions and their own combat experience, the troops’ landing was a cakewalk—almost unopposed. Private First Class Eugene Sledge’s mortar section began singing “Little Brown Jug” at the top of their lungs. He later wrote how he couldn’t believe his good luck: “I didn’t hear a single shot all morning. It was unbelievable.”
Many Marine veterans expected enemy fire at any second. Later that day, General del Valle’s LVT got stuck in a pothole en route to the beach. “It was the worst twenty minutes I’d ever spent in my life,” the general later wrote.
That morning continued to deliver pleasant surprises to the assault force. No mines along the beaches, the main bridge over the Bishi River was still intact, and both airfields were lightly defended. Marines took Yontan Airfield at 1300 while soldiers from the 7th Infantry Division had no problem securing nearby Kadena.
After securing the assault beaches, the landing force left plenty of room for the follow-on forces. Division commanders accelerated the landing of artillery battalions, tanks, and reserves. This massive buildup was hampered by a few glitches. Four artillery pieces went down when their amphibious trucks foundered along the reef. Several other Sherman tanks grounded on the reef. The 3/1 Marines arrived at the transfer line by 1800 but spent an uncomfortable night in their boats because enough LVTs were not available for the last leg at that hour. While only minor inconveniences, by the day’s end, the Tenth Army had 60,000 troops ashore and occupied an expanded beach eight miles long and two miles deep.
The landing was not bloodless. Snipers wounded Major John Gustafson, CO of the 3/5 Marines, later that afternoon. Other men went down to enemy mortars and machine-gun fire. But the Tenth Army’s entire losses (including the hard-luck 2nd Division) were 159 casualties with twenty-eight killed.
This was less than ten percent of casualties suffered by V Amphibious Corps on the first bloody day of Iwo Jima.
Battle of Yae Take
The assault force’s momentum did not slow down after the Tenth Army broke out of the beachhead. The 7th Infantry reached the east coast on the second day. On the third day, the 1st Marine Division secured the Katchin Peninsula and cut the island in two. By now, elements of the III Amphibious Corps had reached their objective initially thought to require eleven days. Colonel Victor Krulak, 6th Marine Division operations officer, recalled General Shepherd’s orders: “Plow ahead as fast as you can. The Japs are on the run.”
Krulak thought: Well hell, we didn’t have them on the run. They weren’t there.
The 6th Division swung north, while the 1st Marine Division moved to the northwest—their immediate problems stemming not from the enemy but a slow supply system still processing on the beach. The reef-side transfer line worked well for troops but not for cargo.
Navy Seabees worked to build a causeway for the reef. At the same time, the 1st Division demonstrated their amphibious know-how learned on Peleliu. They mounted swinging cranes on powered causeways and secured craft to the seaward side of the reef. When boats pulled alongside, cranes lifted nets filled with combat cargo into open hatches of waiting LVTs and amphibious trucks. This worked so well that the division divided its assets within the Tenth Army.
Beach congestion slowed the logistical process. Both Marine divisions used their replacements as shore party teams. Inexperience combined with a constant call for new replacements caused traffic control problems in establishing functional supply dumps and pilferage. This was not new. Other divisions in earlier operations had had the same problems. The quickly advancing divisions desperately needed bulk fuel and motor transport—but these were slow to land and distribute.
The undeveloped road network on Okinawa made this problem worse. Colonel Ed Snedeker, CO of the 7th Regiment in the 1st Marine Division, wrote: “The movement from the west coast landing beaches on Okinawa across the island was difficult because of the rugged terrain. It was physically exhausting for personnel to be on the transports for such a long time. This also presented an initial impossible supply problem in the Seventh’s zone of action because of the lack of roads.”
General Mulcahy brought the Tactical Air Force command post ashore on L +1. Operating out of crude quarters between Kadena and Yontan Airfields, Mulcahy closely watched the Seabees and Army-Marine engineers progress repairing the captured airfields. A Marine observation plane was the first Allied aircraft to land on April 2. Two days later, the airfields were ready to accept fighters. By the eighth day, General Mulcahy could accommodate medium bombers and assumed control of all ashore fleet aircraft.
Mulcahy’s fighter arm, the Air Defense Command, was established on shore under the command of Marine General William Wallace. Graceful F4U Corsairs of Marine Aircraft Group (MAG 31) flew in from escort carriers. Wallace tasked them with flying combat air patrols over the fleet to tackle the vicious mass of kamikaze attacks plaguing the fleet. Most Marine fighter pilots’ initial missions were combat air patrols, while (ironically) Navy squadrons on board escort carriers handled the close air support jobs.
At dawn, Marine Corsairs took off from the airfields and flew combat air patrols over the far-flung fifth fleet. They passed Navy Hellcats coming in from the fleet to support the Marines fighting on the ground. Other air units poured into the two Army airfields: night fighters, torpedo bombers, and an Army Air Forces fighter wing. The Okinawan airfields were not safe-havens. They received nightly artillery fire from long-range bombing the entire first month ashore. But the two airfields remained in operation around the clock. They were an invaluable asset in support of Operation Iceberg.
General Roy Geiger unleashed the 6th Marine Division to sweep north while the 1st Division hunted down and destroyed small bands of enemy guerrillas in the center of the island. Riflemen rode topside on tanks and self-propelled guns streaming northward against the fleeing enemy. Not since Tinian did Marines enjoy such invigorating mobility. On April 7, Marines seized Nagano, the largest town in northern Okinawa. The Navy swept for mines and deployed Underwater Demolition Teams t
o breach obstacles and open the port for direct seaborne delivery of crucial supplies.
Corporal James Day with the 22nd Marines was impressed at the momentum of the operation. He wrote: “Hell, here we are in Nago. It wasn’t tough at all. Up until that time, our squad hadn’t lost a man.” The 22nd Marines continued north through a rugged and broken country. They reached Hedo Misaki at the far end of the island on L +12 after advancing fifty-five miles from the landing beaches at Hagushi.
The honeymoon was coming to a swift end for the rest of the 6th Division. Northwest of Nago, on its bulby nose, the Motobu Peninsula jutted out into the East China Sea. In a six mile area around the 1,200 foot Mount Yae Take, Colonel Takesiko Udo and his Kunigami Detachment were in prepared defensive positions. The delaying tactics were over. Udo’s force comprised two thousand seasoned troops from the 44th Independent Mixed Brigade. He had two rifle battalions, a regimental gun company, and an anti-tank company at his disposal.
Mount Yae Take was a defender’s dream. Steep vines tangled with dense vegetation. Japanese troops booby-trapped the approaches with mines and mounted 20mm machine cannons and heavier weapons deep inside their caves. According to Colonel Krulak: “They were just there. They weren’t going anywhere. They were going to fight to the death. They had a lot of Navy guns that came off disabled ships. They dug them way back in holes where their arc of fire was not more than ten degrees.” An artillery battalion of fifteen Marines had the misfortune to lay their guns directly within the narrow arc of a hidden 150mm cannon. “They lost two howitzers before you could spell cat.”