Perhaps it's worth mentioning some lesser known big achievements of the Manhattan Project. It's not the scientists. It's Hanford and Oak Ridge. Hanford was not only nuclear reactors but a city of more than 43 000 people out of literally nothing. Oak Ridge had the largest building in the world, K-25. It was only surpassed by the Boeing Everett Factory more than twenty years later. These two sites were also the major cost centers of the project. Science is cheap. Enriching uranium and manufacturing plutonium -- especially when no one did it before -- is not.
"At the Hanford Site in south-central Washington state, 177 giant tanks sit below the sandy soil, brimming with the radioactive remnants of 44 years of nuclear-materials production. From World War II through the Cold War, Hanford churned out plutonium for more than 60,000 nuclear weapons. The sprawling enterprise eventually contaminated the soil and groundwater and left behind 212 million liters of toxic waste—enough to fill 85 Olympic-size swimming pools. Decades after the site stopped producing plutonium, the U.S. government is still grappling with how to clean it all up. "
Indeed. Sustained nuclear chain reaction was achieved in Chicago Pile-1 beneath the stands of campus football stadium at the end of 1942. That's when, scientifically, it was proven that the bomb is possible.
Pedantic point, that's when they proved nuclear power was possible. It was still unknown whether the cross section of U-235 was large enough to permit a small, transportable bomb to go critical, and whether that reaction would have occurred fast enough to generate a significant explosion. And in the case of Plutonium, the idea of implosion hadn't even been worked out yet, let alone tested.
By 1942 no one really had doubts about that. I mean, the Einstein–Szilard letter was written in 1939 and Bohr mentioned in lectures also in 1939 the bomb is possible but he didn't think it was possible to produce enough weapons grade uranium within the timeframe of the war. He couldn't foresee, no one could, really, what the US could do when determined.
These details were covered in depth in The Making of the Atomic Bomb by Richard Rhodes. The Oppenheimer movie glosses over a lot of the technical details. It’s worth a read.
We’re also still paying for the enrichment done in the 40s. There are dumps of radioactive material all over the country that were never properly disposed of. Those costs have been externalized on the populations living near those dumps for 80 years now.
The marvel of the Manhattan project, including Hanford and Oak ridge, was the singular focus and short time scale but not necessarily the absolute size.
If we consider just ASML, (the main) supplier of only the EUV machines (and accessories) for manufacturing chips (they don't run the fabs, they just build and maintain the equipment), they also directly employ 42,000 people and utilize another 5,000 tier 1 suppliers. https://en.m.wikipedia.org/wiki/ASML_Holding
That's just the ONE business to make the machines to make the chips, that doesnt include all the folks who make the chips! If we count just one of their customers (TSMC) that's another 70,000+ employees!
National projects are impressive for different reasons than whole industries.
