Seventy years ago today was an Easter Sunday. On 1 April 1945, elements of the United States 10th Army, under General Simon B. Buckner, landed on the island of Okinawa. The landings were almost unopposed, but the 110,000 Japanese defenders soon resisted with the savagery and skill familiar to every US combat leader in the Pacific. Half a million US troops would come ashore in Operation ICEBERG, beginning 82 days of brutal, unrelenting combat for the island. When the battle was finished, General Buckner and one other US General were dead, along with nearly 100,000 of the island’s defenders, and 13,000 US soldiers, sailors, and Marines. (Near the end of the battle, US Marine MajGen Roy Geiger would temporarily command US 10th Army after the death of General Buckner, until Joe Stillwell’s arrival.)
The Japanese had fought furiously, employing in massive waves the kamikaze tactics against the invasion fleet that were first revealed off Leyte. Among the US killed were 4,900 sailors, as the US Navy lost 36 ships sunk and 368 damaged by the suicide onslaught. One in three Japanese civilians were killed or committed suicide in the fighting, nearly 150,000 in total. The battle, which ended with the island being declared secure on 22 June, was a terrifying harbinger of what the invasion of the Japanese Home Islands would be.
The “Saipan ratio” used to compute casualty estimates for the invasion of Japan, was proven a dramatic underestimation by US casualties on Okinawa, which were almost four times the earlier calculations. In addition, Allied intelligence of Japanese air strength on Formosa (within range to help defend Okinawa) had pegged the number of operational aircraft at under one hundred. There was, in fact, eight times that figure, as the US and British Naval forces would discover to their dismay. Okinawa (and Iwo Jima) weighed heavily in the decision to employ atomic weapons against Japan as an alternative to invasion. With what occupation forces found on the Home Islands, the men destined for the invasions Honshu and Kyushu likely breathed a great collective sigh of relief.