JF Ptak Science Books LLC Post 198
Not to be overlooked in this thread on the decision to use the atomic bomb was the long and deadly end-game to the Pacific War planned in pre-use atomic times. The fact of the matter was that semi-defeated Japan (former Prime Minister Konoye told the Emperor privately in February 1945, "I think there is no longer any doubt about our defeat"), was still not remotely close to surrendering, or at least not abiding the possibility of unconditional surrender, in July 1945.
The U.S. plans for the final push on Japan began to form in 1944. It was a massive and complex operation, which was to begin in November 1945, with the aim of subduing the industrial homeland of Honshu, striking a death blow to the teetering ability of the Japanese government to supply civilian goods and metal materiel. The first stage of the attack was called Operation Olympic, and was to take place at Kyushu; but as large as this attack was it was still preliminary to an ever-more massive Operation Coronet—in all, there was to be a 5-million man combined U.S.-Britain invasion army with the largest air and naval support in the history of warfare.
"Hell was upon us, when we lost Saipan," the Chief of the Japanese Naval General Staff told American interrogators shortly after the war. A high-ranking NGS planner explained: "After the Coral Sea and Midway, I still had hope. After Guadalcanal, I felt we could not win, only we would not lose. After the Marianas, we had little chance. After Okinawa, it was all over.”—"Olympic vs. Ketsu-Go", Marine Corps Gazette, August 1965, vol 49 no 8, by Jack Bauer and Alan Coox. For the full article see here.
Whether or not this view was shared with other members of the ruling elite didn’t come into play, as the Japanese high command continued to plan for the defense of the homeland. There were still 2.3 million Japanese armed forces in the islands (53 infantry divisions and 25 brigades); there was also a 2.25 million force of army workers, 1.3 million Navy workers, and a National Volunteer Militia of 28 million. There would be a colossal confrontation along the length and breadth of the country of Japan.
Bauer and Coox continue in their paper (from which I’ll quote at length)
:
“The greatest danger to the assault was assumed to come from the air. The Americans expected opposition from 5,000 kamikazes, a realistic estimate in keeping with Japanese plans (KETSU-GO Operation). These called for 5,000 planes to be expended in attacks on the invasion force, whose appearance was expected sometime after September. The Japanese estimated that the assault force would be carried in 1,000 transports and that if half were sunk in the first ten days the landings could be smashed. Using the 1:6 ratio derived from their Okinawa experience, Japanese planners estimated this would require 3,000 planes. They assigned an additional 350 kamikazes to attacks on the carrier forces. The remaining 1,650 included those under repair and lost before the attack. As late as 15 July, however, only 70% of the required planes were in hand so it seems reasonable to assume that aerial opposition would have been less than expected.
“Covering the Japanese home islands were four ground armies of eight ground divisions (one in Kyushu and five in the Kanto area), plus three brigades, four AAA divisions (with 1200 guns), and 14 cadre divisions.
“From the outset of 1945 the Japanese High command struggled to improve the defensive posture in the homeland where 2 1/2 million men were supposed to confront an invasion. It was hoped to transfer many troops and munitions home from the Asian continent by autumn, but this task grew more difficult with the acceleration of American assaults, and the consequent decrease in Japanese strength. In January 1945 the first joint Army-Navy operational plan was devised, stressing decisive combat in the homeland but the gaining of time through delaying operations on the periphery, especially Okinawa. Surprise and "special attacks" (a euphemism for suicide assaults) were to be the main points of Japanese strategy. The front line of the heartland perimeter would be southern Kuriles-Bonin-Ryukyus-Taiwan-Shanghai. Operational preparations against American landings would be accomplished in the regions of the Kanto, Kyushu, Eastern Sea (Tokai), and South Korea. Particular emphasis would be ascribed to air defense of these districts and the Osaka-Kobe (Hanshin) section. Every effort would be made to destroy the attackers while they were still in the water, in the main battle theater of the Pacific and the East China Sea.
“Immense manpower levies were to be raised, on the basis of the new operational plans, within a few months: 56 divisions, 38 brigades, etc.-involving between 1,500,000 and 2,000,000 new men...with 450,000 men on Kyushu with 220,000 of those (including five field divisions) south of the line Minamata-Nabeoka. An additional three or four divisions were believed available in the northern part of Kyushu as reinforcements while a small additional force could be committed from Honshu. Intelligence estimates, however, predicted that few troops would be committed from Honshu in order to conserve them for the defense of the main island.
“By March 1945 the General Staff had completed an outline for the defense operations (coded as KETSU-GO). All homeland area armies were directed to send their chiefs of staff and key officers to examine the draft informally in Tokyo. Exploiting the terrain of the home islands, and exhorting the fighting spirit and cooperation of the 100 million Imperial subjects, all Navy and Air Force remnants were to tackle the special-attack mission of destroying enemy forces while still at sea. But since Japanese naval power was almost destroyed, and the air units were so weak, homeland ground formations (deployed in depth and massed in decisive battle sectors) would take the offensive against enemy troops who managed to land, and would "recoup in one stroke the declining fate of the Nation."
I mean to point out in all of this that the business of attacking Japan would have been a spectacularly costly and monumental military step, and that his was the major thought in the minds of the American decision makers so far as the military use of the atomic bomb was concerned. Truman had all of this in his head when he authorized the use of the bomb—most of all I am sure he had the hypothesized American casualty reports for these operations, which numbered in the hundreds of thousands and above. The one thing that all of the major decision makers had in their minds at this time, in July 1945, was that the bomb would somehow be employed, one way or another. I’m not aware of any major player having any other thought in his head at this time. (John McCloy was one, but as Asst Secretary of State, he wasn’t a major figure.) So, when one is thinking about The Decision, one certainly has to be aware of the non-bomb, non-surrender military aspect of ending the war, and this is one part of it. (There were some half-million Purple Heart medals made for this invasion in 1945--these Purple Hearts were subsequently awarded to the casualties of the Korean War and through most of the Vietnam War until the 1945 medals were depleted.)