Okinawa, capture of

Okinawa, capture of. Situated 550 km. (340 mi.) from mainland Japan this principal, and central, island of the Japanese Ryūkyū archipelago was assaulted on 1 April 1945 by four divisions of Lt-General Simon Buckner's newly formed Tenth US Army (see Map 79 ).

Ninety-six kilometres (60 mi.) long, Okinawa was a vital air base for any US invasion of mainland Japan. For the Americans it was the most costly and complex operation in the Pacific war, and the last. In sheer magnitude it can only be compared with the Normandy landings (see OVERLORD), with the USA committing a total of over half a million troops and 1,213 warships. The British Pacific Fleet (see Task Force 57) also took part.

Preliminary air and sea bombardments, the occupation of Keise Island and the Kerama Islands, and the clearance of a complicated tangle of beach obstacles by underwater demolition teams (seefrogmen) preceded the landings. Vice-Admiral Turner's Joint Expeditionary Force initially put ashore, on Okinawa's western coast, 1st and 6th Marine Divisions of Maj-General Roy Geiger's 3rd Marine Amphibious Corps, and 7th and 96th Infantry Division of Maj-General John Hodge's 24th Corps. Eventually more than 170,000 US servicemen took part in the island's capture.

Okinawa was strongly defended by 77,000 troops of the Thirty-Second Japanese Army and 20,000 Okinawan militia, and even by local children. Their commander, Lt-General Ushijima Mitsuru, relied on kamikaze pilots to destroy the landings and arranged only a nominal opposition to them. Instead he concentrated almost his entire force inland, around the capital, Naha, and on the northern Motobu peninsula, with the intention of inflicting as many casualties as possible for as long as possible. These tactics, which had been used to a lesser degree on Peleliu and Iwo Jima, enabled the marines to take Kadena and Yontan airfields immediately, for 1st Marine Division to occupy the Katchin peninsula by 4 April, and for 6th Marine Division to break through the Ishikawa isthmus defences on 4 April and reach Nago at the base of the Motobu peninsula three days later while 1st Marine Division moved up the east coast to Aha. However, in the south a stalemate developed when 24th Corps encountered the first of Ushijima's immensely strong defensive positions, which were constructed in rugged, cave-riddled terrain that made them largely immune to air or sea bombardment.

Six days after the landings the C-in-C of the Japanese First Mobile Fleet, Admiral Toyoda, launched his operation TEN-GŌ. Massed kamikaze attacks—called kikusui (floating chrysanthemums) by the Japanese—attacked the American invasion fleet and the Mobile Fleet sailed to attack it, too. Between 6 April and 22 June about 1,900 kamikaze sorties caused unprecedented Allied naval casualties, but the Mobile Fleet was destroyed in the battle of the East China Sea.

Ashore, the marines reached Okinawa's northern tip Hedo Point, in mid-April, and by 20 April 1945 had cleared the Motobu peninsula. Nearby Ie Island was captured by the newly committed 77th Infantry Division, and other offshore islands were also cleared. The marines and 77th Division then reinforced Hodge's corps which, bolstered by the recently landed 27th Infantry Division, had started a major assault on Ushijima's first defensive line on 19 April. This had succeeded and Ushijima, after launching a fierce counter-attack on 4 May, concentrated his forces on a line which ran from Naha through Shuri, the core of his defences, to Yonabaru. Though two badly mauled infantry divisions had to be withdrawn, the extra weight of the marines eventually broke this line. Shuri was abandoned, Naha capitulated on 27 May, and Ushijima fell back on his final defensive position on the Oroku peninsula. Bitter fighting followed, but on 22 June, the day Ushijima committed suicide, Okinawa was declared secure. Of the Japanese garrison only 7,400 survived to become prisoners-of-war. But the Allies also paid a heavy price for Okinawa. Thirty-six warships and landing craft were sunk and 368 damaged; more than 4,900 seamen were killed and 4,824 wounded. Kamikaze pilots caused the most damage, but some was done by mines, bombs (including the first use of the Baka bomb) and explosive motor boats. Marines and infantry also suffered heavily, 7,613 being killed, including Buckner, and 31,807 wounded, while 763 aircraft were lost. See also amphibious warfare.

Bibliography

Gow, I. , Okinawa 1945 (London, 1986).