In the introduction to Leslie Groves’ Now It Can Be Told: The Story of the Manhattan Project, Edward Teller painted a picture of the general. The general himself opens with a foreword:
I have recorded here only that which I am qualified to write about — my own experiences during the development of atomic energy between September 17, 1942, and December 31, 1946, the period during which I was in charge of the Manhattan Project.
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Gradually more and more of the details of our work have been declassified and, with the issuance of an executive order in May, 1959, the curtain was drawn aside on the story of the project.
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The command channels of the Manhattan Engineer District (MED) — the name given to the atomic bomb project — had no precedent. They grew up with the project and were changed as conditions changed. Yet the basic concept — that of always keeping authority and responsibility together — never changed.
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We made certain that each member of the project thoroughly understood his part in our total effort — that, and nothing more.
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Dr. Vannevar Bush, Chairman of the Office of Scientific Research and Development (OSRD), and Dr. James B. Conant, Chairman of the National Defense Research Committee (NDRC), a subdivision of OSRD, were primarily responsible for President Roosevelt’s decision to transform the atomic energy development program from a research project into a program aimed at producing a decisive military weapon. Once the military purpose of the project became governing, Lieutenant General Brehon Somervell, Chief of the Army Services of Supply, and Major General W. D. Styer, his Chief of Staff, entered the picture. Within a few months they brought me in to head up the project, subject, of course, to the personal approval of General Marshall, Secretary of War Stimson, and, finally, the President.
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At first, I was responsible only for the engineering, construction and operation of the plants to produce bomb materials. Had our work been routine and clearly defined, my responsibility probably would have ended there. However, it soon became evident to Dr. Bush and to me that if serious delays to our work were to be avoided the MED should expand its research activities, and take over control of all the atomic research projects then under the management of the OSRD, thus uniting authority with responsibility. This transfer was effected without friction during the fall and winter of 1942 by the simple device of allowing the OSRD contracts to continue in force until they expired, at which time they were replaced by new ones in which the MED was the contracting agency. The transition was so smooth, indeed, that, as I have read accounts of that period by some of the people involved, I have been struck by the fact that they did not seem to be aware of just when the transfer of authority actually took place.
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Thus I became responsible, particularly to General Marshall, Secretary Stimson and President Truman, for the over-all success of the use of the bomb against Japan. This assignment included selecting the target cities, subject to the approval of the Chief of Staff and the Secretary of War; preparing the orders and instructions for the bombing operations; and arranging for Army and Navy units to provide the necessary support to our overseas effort.