360 miles from Japan proper (Kyushu) and 330 miles from Formosa. It is the largest of the Ryukyu island chain, the Nansei Shoto or South Western islands in the East China Sea.
3. Geography. Okinawa is a large island, 60 miles long and three to ten miles in width. Topography is varied, woods, marshes, mountains, hills, cliffs and ravines, as well as flat terrain, including good sites for airfields. In 1945 it had a deep harbor at Naha, the capital, and two fleet anchorages on the east coast. The northeastern part of the island is more rugged and sparsely populated, the southwest densely populated.
4. Military objectives and rationale. The principal American objective in seizing Okinawa was to secure a staging area for the planned subsequent invasion of the Japanese mainland. According to Gow, "only Okinawa . . . could accommodate sufficient airfields and naval anchorages as well as adequate space to stage a massive concentration of ground forces for an invasion of the Japanese mainland." The American Joint Chiefs of Staff ordered Admiral Chester Nimitz, Commander in Chief Pacific Fleet Ocean Areas, "to occupy one or more positions in the Nansei Shoto, target date 1st March 1945." As early as October 1943, Formosa and Okinawa were envisaged as alternative springboards for the final invasion of Japan, but in the summer and fall of 1944 "senior American commanders in the Pacific expressed some doubt that the Formosa operation was practicable." The Formosa option was originally favored by Chief of Naval Operations Admiral Ernest King; however, after General Douglas MacArthur convinced President Franklin Roosevelt that the United States should invade the Philippines and the Japanese summer 1944 offensive in southern China overran B-29 air fields there, King acquiesced in the recommendation of Admiral Raymond Spruance that Iwo Jima and then Okinawa should be the U.S. Navy's principal targets in the Western Pacific in the sprin...