The Making of the Atomic Bomb

account of his career, Speaking Frankly, narrates an entire chapter about Potsdam without once mentioning Stimson's name, relegating his rival to a brief separate discussion of the decision to use the atomic bomb on Japan and awarding him there the dubious honor of having chosen the targets. In fact, Stimson at Potsdam would be reduced to serving Truman and Byrnes as not much more than a messenger boy. But the messages he brought were fateful.

“We reviewed the Second Armored Division,” Truman reports his Berlin tour in his impromptu diary, “… Gen. [J. H.] Collier, who seemed to know his stuff, put us in a reconnaissance car built with side seats and no top, just like a hoodlum wagon minus the top, or a fire truck with seats and no hose, and we drove slowly down a mile and a half of good soldiers and some millions of dollars worth of equipment — which had amply paid its way to Berlin.” The destroyed city fired an uneasy burst of associations:

Then we went on to Berlin and saw absolute ruin. Hitler's folly. He overreached himself by trying to take in too much territory. He had no morals and his people backed him up. Never did I see a more sorrowful sight, nor witness retribution to the nth degree…

I thought of Carthage, Baalbec, Jerusalem, Rome, Atlantis; Peking, Babylon, Nineveh; Scipio, Rameses II, Titus, Hermann, Sherman, Jenghis Khan, Alexander, Darius the Great. But Hitler only destroyed Stalingrad — and Berlin. I hope for some sort of peace — but I fear that machines are ahead of morals by some centuries and when morals catch up perhaps there'll be no reason for any of it.

I hope not. But we are only termites on a planet and maybe when we bore too deeply into the planet there'll be a reckoning — who knows?

The “Proposed Program for Japan” that Stimson had offered to Truman on July 2 had reckoned up that country's situation — which included the possible entry of the Soviet Union, at present neutral, into the Pacific war — and judged it desperate:

Japan has no allies.

Her navy is nearly destroyed and she is vulnerable to a surface and underwater blockade which can deprive her of sufficient food and supplies for her population.

She is terribly vulnerable to our concentrated air attack upon her crowded cities, industrial and food resources.

She has against her not only the Anglo-American forces but the rising forces of China and the ominous threat of Russia.

We have inexhaustible and untouched industrial resources to bring to bear against her diminishing potential.

We have great moral superiority through being the victim of her first sneak attack.

On the other hand, Stimson had argued, because of the mountainous Japanese terrain and because “the Japanese are highly patriotic and certainly susceptible to calls for fanatical resistance to repel an invasion,” America would probably “have to go through with an even more bitter finish fight than in Germany” if it attempted to invade. Was there, then, any alternative? Stimson thought there might be:

I believe Japan is susceptible to reason in such a crisis to a much greater extent than is indicated by our current press and other current comment. Japan is not a nation composed wholly of mad fanatics of an entirely different mentality from ours. On the contrary, she has within the past century shown herself to possess extremely intelligent people, capable in an unprecedentedly short time of adopting not only the complicated technique of Occidental civilization but to a substantial extent their culture and their political and social ideas. Her advance in these respects… has been one of the most astounding feats of national progress in history…

It is therefore my conclusion that a carefully timed warning be given to Japan…

I personally think that if in [giving such a warning] we should add that we do not exclude a constitutional monarchy under her present dynasty, it would substantially add to the chances of acceptance.

Within the text of his proposal the Secretary of War several times characterized it as “the equivalent of an unconditional surrender,” but others did not see it so. Before Byrnes left for Potsdam he had carried the document to ailing Cordell Hull, a fellow Southerner and Franklin Roosevelt's Secretary of State from 1933 to 1944, and Hull had immediately plucked out the concession to the “present dynasty” — the Emperor Hiro-hito, in whose mild myopic figure many Americans had personified Japanese militarism — and told Byrnes that “the statement seemed too much like appeasement of Japan.”

It may have been, but by the time they arrived in Potsdam, Stimson, Truman and Byrnes had learned that it was also the minimum condition of surrender the Japanese were prepared to countenance, whatever their desperate situation. U.S. intelligence had intercepted and decoded messages passing between Tokyo and Moscow instructing Japanese ambassador Naotake Sato to attempt to interest the Soviets in mediating a Japanese surrender. “The foreign and domestic situation for the Empire is very senous,” Foreign Minister Shigenori Togo had cabled Sato on July 11, “and even the termination of the war is now being considered privately… We are also sounding out the extent to which we might employ the USSR in connection with the termination of the war… [This is] a matter with which the Imperial Court is… greatly concerned.” And pointedly on July 12:

It is His Majesty's heart's desire to see the swift termination of the war… However, as long as America and England insist on unconditional surrender our country has no alternative but to see it through in an all-out effort for the sake of survival and the honor of the homeland.

Unconditional surrender seemed to the Japanese leadership a demand to give up its essential and historic polity, a demand that under similar circumstances Americans also might hesitate to meet even at the price of their lives: hence Stimson's careful qualification of his proposed terms of surrender. But to the extent that the imperial institution was tainted with militarism, an offer to preserve it might also seem an offer to preserve the militaristic government that ran the country and that had started and pursued the war. Certainly many Americans might think so and might conclude in consequence that their wartime sacrifices were being callously betrayed.

Hull considered these difficulties while Byrnes sailed the Atlantic and sent along a cable of further advice on July 16. The Japanese might reject a challenge to surrender, the former Secretary of State argued, even if it allowed the Emperor to remain on the throne. In that case not only would the militarists among them be encouraged by what they would take to be a sign of weakening Allied will, but also “terrible political repercussions would follow in the U.S… Would it be well first to await the climax of Allied bombing and Russia's entry into the war?”

The point of warning the Japanese was to encourage an early surrender in the hope of avoiding a bloody invasion; the trouble with waiting until the Soviet Union entered the war was that it left Truman where he had dangled uncomfortably for months: over Stalin's barrel, dependent on the USSR for military intervention in Manchuria to tie up the Japanese armies there. Hull's delaying tactic might improve the first prospect; but it might also secure the second.

Another message arrived in Potsdam that evening, however, that changed the terms of the equation, a message for Stimson from George Harrison in Washington announcing the success of the Trinity shot:

Operated on this morning. Diagnosis not yet complete but results seem satisfactory and already exceed expectations. Local press release necessary as interest extends great distance. Dr. Groves pleased. He returns tomorrow. I will keep you posted.

“Well,” Stimson remarked to Harvey Bundy with relief, “I have been responsible for spending two billions of dollars on this atomic venture. Now that it is successful I shall not be sent to prison in Fort Leavenworth.” Happily the Secretary of War carried the cable to Truman and Byrnes, just returned to Potsdam from Berlin.

In Stimson's welcome news Byrnes saw a more general reprieve. It informed his overnight response to Hull.