T. A. Gardner
Thread Killer
Enrico Fermi, an Italian that left because of Mussolini, had more impact on the Manhattan Project than Einstein. Einstein's primary role was being a celebrity of sorts and putting his name and weight behind the effort to get FDR to approve the project.
The German program failed for a variety of reasons. One major one was, unlike the US, German industry was unable to produce boron free graphite, something US chemists and industrial leaders were able to do in short order. This made building a working reactor possible in the US in a matter of a few years versus Germany where they went the heavy water route and never got to a working reactor. Notably, the US knew about the heavy water route and not only produced exponentially more heavy water that Germany (the US program dwarfed the German one) but they produced several heavy water reactors for research use by 1943.
On production of uranium ore for refining into weapons grade material, the US by 1941 was producing more refined ore a day than Germany was in a year. The US program was not only massively larger, but again, US chemists and engineers figured out new processes that made refining the ore faster and easier to do.
At Oak Ridge the electromagnetic separation of U-235 from refined ore in the form of Uranium hexafluoride, consumed 6000 tons of silver to make the coils (copper was a restricted war material) initially and used 14,700 tons eventually.
Of note, the Manhattan Project in terms of cost was relatively small compared to some other US wartime projects such as the B-29, building Liberty and Victory ships, or the construction of destroyer escorts to fight the U-boats.
