But it took a long time to light a fire under the American authorities, and it wasn't until the absolutely critical replacement of his name is a footnote in history with Groves that things really got rolling, on the industrial scale needed, and the scientists and engineers sufficiently focused on the design and execution of the bombs themselves (which for various reasons didn't end up being the afterthought some expected). And he of course picked Oppenheimer to lead that effort, which was opposed by most, albeit he was one of the few uncommitted physicists capable at that level.
These two men organized more than 100,000 people for the industrial production of the required fissionables (90% of the work per Wikipedia), and Grove's drive got those ready in time to forestall Operation Downfall. Heck, they went from the first real test to putting metal on target in 21 and 24 days....
And the design and fabrication of "the bomb" turned out to be massively harder than they expected due to weapons grade plutonium not being suitable for a gun assembly bomb (which is also grossly wasteful of fissionable, if the Little Boy is any guide, as I recall it had 3x critical mass, and a fair amount if it wasn't as pure U-235 as they'd have wanted). Making the implosion concept work was hard, and they got it right the first time....
Read Rhode's book, especially the latter half after the nuclear physics discoveries take a back seat (https://www.amazon.com/Making-Atomic-Bomb-25th-Anniversary/d...) and Grove's autobiography (https://www.amazon.com/Now-Can-Be-Told-Manhattan/dp/03068018...) to learn the organization and management details, they're amazing.
And had much wider effects on the world at large, that we could indeed do such things led to the Apollo program, and of course to too much conceit that "If we can put a man on the moon, why can't we [do something very different and a lot more intractable, probably without even a clearly defined goal]?"
More later, or email me (check my HN profile).
It's an excellent read, cover-to-cover. One of the few assigned books I read with excitement while in undergrad.
The science was so good that I got a bad grade on my History class paper, because I focused too much on the science and not so much on the "storytelling" of history. Which apparently puts me in good company slongside Knuth :-)
J. Robert Oppenheimer and Leslie Groves were a fascinating team, Oppenheimer being a physicist and Groves an Army general.
A must for anyone in technical management.
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