Presidential Predicaments: I. Truman - On Approach to Hiroshima
For almost all of World War II, Harry Truman was a United States Senator from Missouri. In January 1945, he was inaugurated as Franklin Roosevelt’s Vice-President. Just over three months later, on April 12, 1945, Roosevelt died and Harry Truman became President of the United States.
Until he became President, Truman had known nothing of the Manhattan Engineering District, also known as the Manhattan Project—the U.S. effort to develop an atomic bomb. Members of Congress had been told nothing about it. Nor had the Vice-President.
The day after he became President, Truman was briefed on the atomic bomb project for the first time, in general terms, by Secretary of War Henry Stimson. Twelve days later, he was briefed on it in more detail by Stimson and General Leslie Groves, the military director of the Manhattan Project. We don’t have any record of what Truman was told in these briefings. At this point the success of the project had begun to seem likely. We may assume he was told at least that.
What do you suppose he was told or understood about the effects of the new bomb? President Truman had served in combat in World War I as an artillery officer. He had experience with military explosives. More recently, he no doubt had learned about the “strategic” bombing the allies were conducting in Germany on targets like bridges, dams, railroads, and oil refineries. This “strategic” bombing was something new in war. It had become commonplace for the first time only in World War II.
He might also have been told something about the firebombing that General Curtis LeMay and the Army Air Force had been conducting in Japan since March. By April these attacks had burned down tens of Japanese cities and killed hundreds of thousands of their inhabitants. Secretary of War Stimson certainly knew about these attacks. He had been troubled by them because they weren’t “strategic” attacks. While they might destroy some military targets, they just destroyed, in the last analysis, cities and the people in them. They were a kind of what was called “area” bombing.
As the Secretary of War, Stimson could have stopped the firebombing. He hadn’t. LeMay was still conducting firebombing raids.
We have to think that the scientists in the Manhattan Project knew more about what the effects of the new bomb would be than anyone else did, both the scale of the destruction that would be caused and that damage would be caused by the new thing this bomb would generate, ionizing radiation.
Just what that ionizing radiation would do was still largely unknown.
In both areas, the scientists’ knowledge was theoretical. No one had yet seen or experienced what an atomic bomb would do.
Before the first test of the atomic bomb, the scientists at Los Alamos had set up a pool to predict the yield. Predictions ranged widely. The low estimate was the equivalent of a few thousand tons of the conventional explosive TNT, still orders of magnitude greater than the yield of any conventional weapon we had. Estimates went from there up to the equivalent of twenty thousand tons of TNT.
A few scientists thought the bomb might set the earth’s atmosphere on fire. The risk of this happening was not large, most agreed, but it was a real risk. How big would you think the risk of setting our atmosphere on fire could be before the test would appear to be a risk not worth taking?
In Truman’s second briefing, Stimson and Groves had recommended that a committee of leaders and scientists from the Manhattan Project be put together to deliberate and advise the President on matters concerning the new bomb. Questions for the Committee would be, for example, whether to use the weapon in the war. And if so, how. And, because of some proposals that had earlier been brought by the physicist Niels Bohr to President Roosevelt and apparently well-received by him, whether to use it at all, even in a test, before an effort had been made to build trust with the Soviets.
Truman approved the creation of this “Interim Committee” to exist until Congress was able to put together something more permanent to oversee the issues raised by atomic energy. On May 1, three weeks after Truman became president, the Committee was constituted. Stimson was to be its chair. A Scientific Subcommittee of Manhattan Project scientists was created to serve as consultants to the Interim Committee. J. Robert Oppenheimer, the director of the laboratory in Los Alamos where the bomb was being designed, was made chair of the Scientific Subcommittee.
On May 8, less than a month after FDR died and Truman became President, Nazi Germany surrendered. The Interim Committee met formally for the first time the next day. The new kind of bomb would not be needed now in the war with Nazi Germany. If it were used, it would be used on Japan.
We’d been worried that the Germans might develop an atomic bomb. We’d not been worried that Japan would.
The committee seems not to have seriously considered the idea that the new bomb might not be used at all on Japan, even though by now we’d effectively blockaded Japan and it was almost certainly destined for defeat. We’d still probably have to invade the country and some of our soldiers would die, no one could tell you for sure how many. Some estimates were low, some were quite high. Many Japanese would die also. More Japanese than Americans but estimates varied widely here too.
The idea of conducting a demonstration drop, not on a city but somewhere that would allow the weapon’s effects to be clearly seen by the Japanese, was seriously considered, and rejected. What if the bomb didn’t work in the demonstration?
In a meeting of the Interim Committee on June 1, six weeks after Truman had become President and six weeks before an atomic bomb was exploded for the first time in a test, the Committee was joined by several important American industrialists. In this meeting, the Committee adopted a recommendation about use of the bomb. It recommended that the bomb be used “against Japan as soon as possible…on a war plant surrounded by workers’ homes…without prior warning.”
What the Committee recommended, let’s notice, is a “strategic” use of the bomb, a military use on “a war plant surrounded by workers’ homes.” The Committee seems to have assumed that this kind of use was possible. The recommendation also called for no warning to be given. The idea here was probably to make the experience as shocking as possible for those went through it.
Jimmy Byrne, a businessman from South Carolina, was an advisor to President Truman and Truman’s representative on the Interim Committee. He was about to become Truman’s first Secretary of State. Byrne carried the Committee’s recommendation to President Truman the same day.
Our Soviet allies had been told nothing about the Manhattan Project. Some of the scientists and leaders of the Manhattan Project had argued that certain scientific knowledge about the bomb could safely be shared with the Soviets as a means of building a platform of trust that might lead to further cooperation and prevent an arms race after the war. The scientific knowledge, they pointed out, should not be considered ‘secret.’ It was available to any decent physicist. Certain kinds of practical technical knowledge—like how to enrich uranium or manufacture plutonium--might be withheld until trust was established. That knowledge also wasn’t something that could be kept secret for long, the scientists said.
On the Committee, Jimmy Byrne had argued against any sharing of knowledge concerning the bomb with the Soviets. Having a monopoly on the atomic bomb after the war would allow us, Byrne had argued, to “dictate our own terms.” That’s the way he saw it.
We have no record of President Truman’s response to the recommendation of the Interim Committee. Nor do we know whether President Truman had been given an opportunity to consider the ideas about dealing with the Soviets that had been presented to FDR by Niels Bohr and to the Interim Committee by some of the Manhattan Project scientists.
On July 16, 1945, three months after President Truman came into the office, six weeks after he received the recommendation from the Interim Committee about use of the atomic bomb on Japan, the first bomb that used nuclear energy was successfully detonated at the newly established White Sands Proving Grounds in southern New Mexico.
President Truman didn’t witness the test. He didn’t have the chance to see what the new bomb could do. On that day, July 16, 1945, he was in Potsdam, a city in eastern Germany, at a conference convened by the victorious allied powers to decide what to do with the defeated Axis powers—Germany and Italy—and the territories they had occupied.
Has any U.S president ever witnessed the test of a nuclear bomb?