g of 1945.
The Japanese did little to reinforce the Ryukyus before March 1944; however, after the fall of Saipan in June 1944, the first serious American penetration of Prime Minister Hideki Tojo's 'Absolute National Defence Zone,' the Belotes said that "a leisurely build-up of Okinawa's defenses was out." Under the October 1944 Sho-Go Plan, the decision was taken to strengthen the inner defenses of the Empire, including the Ryukyus. Although the Japanese did not know where the Americans would strike next, reinforcement of Okinawa was accelerated in March 1945 following the American landings on Iwo Jima. The aim of the Ten-Go plan jointly adopted by army and navy planners on February 6, 1945 was to concentrate "all Army and Navy forces in the East China Sea", especially air strength, in order to "crush any enemy attempt to invade points within this area."
5. Command Structure. Nimitz was in overall command of the Okinawa invasion named Operation Iceberg. His Covering Force was the Fifth Fleet under Spruance,
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