JF Ptak Science Books Post 1720
July 17, 1945 (Trinity +1 or Hiroshima -20), the day after the Trinity test of the first atomic weapon, was the first day in which very concerted, very real discussions ensued about what to do with the bomb and where to us it. Actually the discussions were mostly on the “where” than on the “whether”. (As it turns out part of a minor segment of the “whether” part was Leo Szilard’s petition to President Truman not to use the bomb and which was signed by 155 Manhattan Project scientists, and which had reached its final version on this day.)
The truth of the matter was that it was a very complex issue, an easily misunderstood tapestry of circumstance and consequence. The major issue of course was that the Japanese would not surrender, and that there would be “fanatical resistance” once the invasion of the Japanese islands had begun. The battle of Okinawa had just been fought—it was a horrible confrontation taking 12,5000 American lives and more than 1000,000 Japanese , demonstrating that even in impossible circumstances that the Japanese simply would not surrender (unconditionally). This is just one instance—there are many others, not the least of which was t he recent firebombing of Tokyo, taking 150,000 lives. Air strikes in general seemed to not make a difference in the will of Japan to fight—as was demonstrated again and again in the British and American bombing of Germany—as was further demonstrated in General Curtis LeMay’s and General Hap Arnold’s 60-city attack in the May-August span. The thought was that if there was an invasion that it could well cost the U.S. 1000,000+ casualties and would be completely devastating to Japan.
One issue concerned the Soviet Union breaking their neutrality by invading Manchuria (scheduled for 16 August according to American intelligence reports) and entering the war against the Japanese, creating a northern front and an impossible position for the Japanese. Another issue regarded the Soviets brokering a truce—revealed on 12 July to the American administration through intercepted communications between Moscow and Tokyo—between the U.S. and Japan. In both circumstances the issue of the unconditional truce that was demanded by the Americans could well have been made impossible and bartered out.
Over the next few days the Potsdam Conference would come to an end, and the Japanese would reject the orders of surrender two days after that. On 21 July the approval to use the bomb was made by Truman and sent along to Secretary of War Henry Stimson on the 24th. One day later the only written order to use the bomb would be sent by acting chief of staff of the Joint Chiefs Thomas Handy to General Carl Spaatz, Commander of the US Army Strategic Air Force. Targets were selected (with General Groves clinging to his desire to bomb Kyoto, a spectacularly bad choice, which I believe was also the choice of John von Neumann). Nagasaki was not yet on the list but would be in a few days. By the end of July Hiroshima is chosen as the first target—one reason being that there were no American POW camps located in the city (as was the case with the other two pre-Nagasaki selections).
Returning to the “whether” part—it is perhaps surprising to see the list of people who had great reservations about using the bomb (at all). Dwight Eisenhower was one of them, and he wrote about his distaste for using the bomb against Japan in his book Mandate for Change:
"...in [July] 1945... Secretary of War Stimson, visiting my headquarters in Germany, informed me that our government was preparing to drop an atomic bomb on Japan. I was one of those who felt that there were a number of cogent reasons to question the wisdom of such an act. ...the Secretary, upon giving me the news of the successful bomb test in New Mexico, and of the plan for using it, asked for my reaction, apparently expecting a vigorous assent.
"During his recitation of the relevant facts, I had been conscious of a feeling of depression and so I voiced to him my grave misgivings, first on the basis of my belief that Japan was already defeated and that dropping the bomb was completely unnecessary, and secondly because I thought that our country should avoid shocking world opinion by the use of a weapon whose employment was, I thought, no longer mandatory as a measure to save American lives. It was my belief that Japan was, at that very moment, seeking some way to surrender with a minimum loss of 'face'. The Secretary was deeply perturbed by my attitude..." - Dwight Eisenhower, Mandate For Change, pg. 380
Eisenhower also had no stomach for the United States to be the first country to use “that thing”.
Another was Admiral William Leahy (Chief of Staff to Presidents Franklin Roosevelt and Harry Truman), who weighed in strongly with the following "It is my opinion that the use of this barbarous weapon at Hiroshima and Nagasaki was of no material assistance in our war against Japan. The Japanese were already defeated and ready to surrender because of the effective sea blockade and the successful bombing with conventional weapons.” --William Leahy, I Was There, pg. 441.
The list is quite long, and includes people like General MacArthur, John J. McCloy (assistant Secretary of War), Joe Grew (Under Secretary of State) , Paul Nitze, Lewis Strauss, Albert Einstein, and more. General Spaatz, who received the one written order to use the bomb, wrote later "If we were to go ahead with the plans for a conventional invasion with ground and naval forces, I believe the Japanese thought that they could inflict very heavy casualties on us and possibly as a result get better surrender terms. On the other hand if they knew or were told that no invasion would take place [and] that bombing would continue until the surrender, why I think the surrender would have taken place just about the same time."
Its impossible really to do any justice to this issue in a thousand words, and impossible to try and recreate the atmosphere of those few weeks; it is also impossible to imagine (unless you lived it) the cast relief of the many millions of people who woke up on 7 August to the news of the destruction of Hiroshima. And of course the Japanese still didn’t surrender until after the use of the second bomb on 9 August against Nagasaki. And so on.
They were 20 very full days.
For further quotes on those having reservations about using the bomb see Doug Long's very useful site.
Also, the names of the 69 signers, gathered from Gene Danan's website, here.