Scott,
Thank you for this information. While reviewing other sources related to the topic, the picture becomes quite large. I have read other Air Force related books which do not contain citations but did provide important clues for further research. And to point out inconsistencies.
A memorandum from James F. Byrnes dated March 2, 1945 was sent to President Roosevelt. It indicated the amount of money spent on the Manhattan project and added ... "with no definite assurance yet of production." He suggested a project review. FDR Library, Hyde Park, New York.
Other information without citations was published by others. I generally put such information aside but keep it in mind in case a missing piece appears. The Atomic Bombs were a mechanical engineering and chemical engineering problem. The US chose DuPont de Nemours to handle the plutonium side of things.
I suggest those interested try the Defense Technical Information Center. Sometimes, certain documents ended up in logical places to look while others ended up in, let's say, out of the way places.
http://www.dtic.mil/dtic/about/about.html
For the most part, the invasion commanders knew little about atomic bombs. They were part of the planning under the category of very powerful bombs that would be used just behind the enemy beaches to kill troops and destroy supplies, or damage one or more specific targets. The February 1951 issue of Popular Science introduced the public to Radiological Weapons like "Death Sand." Troops running through it would be poisoned. Our troops as well as the Japanese. The article cites a 12 page report produced by the Department of the Army and "recently" published in Officers' Call, an official, monthly Army publication.
Best,
Ed