Vannevar Bush headed the U.S. Office of Scientific Research and Development (OSRD) during World War 2, and General Groves admits that Dr. Bush was quite disturbed at Groves’ appointment as head of the Manhattan Project, as he explains in Now It Can Be Told: The Story of the Manhattan Project, because he felt Groves was too aggressive and might have difficulty with the scientific people. After their first inauspicious meeting, Groves went back to his office:
Finding my secretary, Mrs. O’Leary, there, I told her I was being reassigned and that if she wanted to come along, I would be glad to have her. I added, in what proved to be a great understatement, that this would be a very quiet and easy job for her and she should be sure to bring along some knitting to keep herself occupied. This prediction proved valid for about two days.
When I returned home that evening I told my wife and daughter and wrote to my son, a cadet at West Point, that I had a new job, that it involved secret matters and for that reason was never to be mentioned. The answer to be given if they were asked what I was doing was, “I don’t know, I never know what he’s doing.” To my son, I added, “If it is an officer who knows me well, and he is persistent, you can add, ‘I think it’s something secret.’”
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Unlikely as it may seem to many people, they first learned of the nature of my assignment at the same moment, three years later, that the bombing of Hiroshima was announced to the rest of the world.