In September, 1942, Leslie Groves was serving as Deputy Chief of Construction of the Army Corps of Engineers, overseeing all Army construction, at home and abroad, but he wanted to get in on the real action. Instead, as he explains in Now It Can Be Told: The Story of the Manhattan Project, he was offered a role in Washington:
“I don’t want to stay in Washington.”
“If you do the job right,” Somervell said, “it will win the war.”
My spirits fell as I realized what he had in mind. “Oh, that thing,” I said.
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Though a big project, it was not expected to involve as much as $100 million altogether. While this was more than the cost of almost any single job under my jurisdiction, it was much less than our total over-all spending in a normal week.
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“The basic research and development are done. You just have to take the rough designs, put them into final shape, build some plants and organize an operating force and your job will be finished and the war will be over.”
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In the course of our discussion, we agreed that, because the Pentagon was so nearly finished and because I had had so much to do with it, I would continue to control its construction, despite my new assignment. There were two reasons for this. First, my sudden disappearance from the work on the Pentagon would attract much more notice than would my absence from my other Army construction activities. Second, because of the natural interest in the Pentagon displayed by a number of Congressmen, it would be better for me to continue to carry the responsibility for that job than to pass it on to someone else who was unfamiliar with its past problems and their many political ramifications.
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I thought that there might be some problems in dealing with the many academic scientists involved in the project, and I felt that my position would be stronger if they thought of me from the first as a general instead of as a promoted colonel. My later experiences convinced me that this was a wise move; strangely enough, it often seemed to me that the prerogatives of rank were more important in the academic world than they are among soldiers.
At the time I was brought into the picture, research on the uses of atomic energy had been going on at a gradually accelerating pace since January, 1939, when Lise Meitner explained that the uranium atom could be split.
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Virtually all laboratory research until this time had been aimed at achieving a controlled chain reaction, using U-235, a rare isotope of uranium which comprises less than one percent of the metal in its natural state. This isotope has the property of fissioning readily—a property which the far more abundant form of uranium, U-238, does not display. But it soon became apparent that unless unprecedented quantities of this material could be produced in a much purer state, a U-235 chain reaction would be impossible. The basic problem was to arrive at an industrial process that would produce kilograms of a substance that had never been isolated before in greater than sub-microscopic quantities.
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The way for a major breakthrough was open as a result of studies that suggested the theoretical feasibility of transmuting U-238 into a highly fissionable new element, plutonium, which might then be separated from the parent uranium by chemical means. The hope was that this would be easier to do than to isolate or concentrate the rare U-235 by physical means. The group headed by Dr. Glenn T. Seaborg at the University of California undertook to prepare extremely small amounts of plutonium, and in March of 1941 succeeded in creating the first submicroscopic amounts of Plutonium-239. Later that month the California group confirmed the theory that under neutron bombardment plutonium atoms fissioned as readily as atoms of U-235.
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The entry of the United States into World War II caused the abandonment of all projects aimed at developing atomic energy as a source of power and gave added impetus to the efforts to build an atomic bomb.
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It is to their everlasting credit that Bush and his colleagues had the discernment to recognize the limitations of their own organization as well as the moral fortitude to admit them in the national interest. Very few men, confronted with a similar situation, would have done so.
Consequently, when the Top Policy Group met on December 16, 1941, Bush recommended that the Army Corps of Engineers carry out the construction work, and asked that a competent Army officer become thoroughly familiar with the project.
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When the Corps of Engineers started its work, its job was simply to build and operate the production plants. The problems involved in the development of the bomb and its delivery were for the time being largely ignored.
Nor was the full magnitude of the project generally appreciated. No one thought of it as entailing expenditures running into the billions of dollars.
I’m deeply interested in this.