Ushijima’s naval component consisted of the Okinawa Naval Base Force, the 4th Surface Escort Unit, and various naval aviation activities all under the command of Rear Admiral Minoru Ota. In this combined command were approximately 10,000 men, of whom only 35 percent were regular naval personnel. The remainder were civilian employees belonging to the different sub-units of the Naval Base Force. Part of Ota’s command consisted of torpedo boat, suicide boat, and midget submarine squadrons at the Unten-Ko base on Motobu Peninsula.
Rounding out the Thirty-second Army was a native Okinawan home guard, whose members were called Boeitai. These men were trained by the army and were to be integrated into army units once the battle for Okinawa was joined. The Boeitai provided Ushijima with 17,000–20,000 extra men. Added to this group were 1,700 male Okinawan children, 14 years of age and older, who were organized into volunteer youth groups called “Blood and Iron for the Emperor Duty Units,” or Tekketsu—Benis M. Frank
L-Day and Movement to Contact
Operation Iceberg got off to a roaring start. The few Japanese still in the vicinity of the main assault at first light on L-Day, 1 April 1945, could immediately sense the wisdom of General Ushijima in conceding the landing to the Americans. The enormous armada, assembled from ports all over the Pacific Ocean, had concentrated on schedule off Okinawa’s southwest coast and stood coiled to project its 182,000-man landing force over the beach. This would be the ultimate forcible entry, the epitome of all the amphibious lessons learned so painstakingly from the crude beginnings at Guadalcanal and North Africa.
Admiral Turner made his final review of weather conditions in the amphibious objective area. As at Iwo Jima, the amphibians would be blessed with good weather on the critical first day of the landing. Skies would be cloudy to clear, winds moderate east to northeast, surf moderate, temperature 75 degrees. At 0406 Turner announced “Land the Landing Force,” the familiar phrase which marked the sequential countdown to the first assault waves hitting the beaches at H-Hour. Combat troops already manning the rails of their transports then witnessed an unforgettable display of naval power—the sustained bombardment by shells and rockets from hundreds of ships, alternating with formations of attack aircraft streaking low over the beaches, bombing and strafing at will. Enemy return fire seemed scattered and ineffectual, even against such a mass of lucrative targets assembled offshore. Turner confirmed H-Hour at 0830.
Department of Defense Photo (USMC) 116412
Taking part in the prelanding bombardment of Okinawa was the Idaho (BB 42), blasting away at the island with her 14-inch guns at preselected targets. As the troops landed, naval gunfire ships let loose with rolling barrages which cleared the way.
Now came the turn of the 2d Marine Division and the ships of the Diversionary Force to decoy the Japanese with a feint landing on the opposite coast. The ersatz amphibious force steamed into position, launched amphibian tractors and Higgins boats, loaded them conspicuously with combat-equipped Marines, then dispatched them towards Minatoga Beach in seven waves. Paying careful attention to the clock, the fourth wave commander crossed the line of departure exactly at 0830, the time of the real H-Hour on the west coast. The LVTs and boats then turned sharply away and returned to the transports, mission accomplished.