Don’t Worry – It Can’t Happen (1940) [pdf]
gwern.net
gwern.net
I'll just say now what I said then (https://news.ycombinator.com/item?id=13905409):
This is not as silly an article as it may appear to be in hindsight. When it appeared (in May 1940: https://www.scientificamerican.com/article/dont-worry-it-can...), most scientific authorities, including such non-idiots as Niels Bohr, believed that, while an atomic chain reaction was theoretically possible, the only way an it could be achieved was by bringing together a quantity of nuclear fuel so large as to make the effort impractical.
The first proof that this was not in fact the case came in the Frisch-Peierls memorandum (https://en.wikipedia.org/wiki/Frisch%E2%80%93Peierls_memoran...), which had been written two months before Harrington's article appeared, but which was highly classified and thus out of reach of pop-science journalists. Frisch and Peierls' figures indicated that a critical mass could be achieved with just one kilogram of uranium-235; this turned out to be an underestimate, but not so much as to invalidate their fundamental point, which was that criticality could be achieved with a mass of fuel small enough to be delivered by a 1940s-era airplane.
This came as news to the brightest lights in the world of physics, up to and including Albert Einstein, so it's probably unfair to expect a contemporary writer for Scientific American to be further ahead in the science than they were.
Fission went from initial discovery to wrecking cities in only seven years. It’s like if Ben Franklin started out flying a kite in a thunderstorm and ended up creating a smartphone.
The entire idea that atomic bombs were ever
manufactured, let alone used, is absolutely
ludicrous. There have never been any atomic
bombs deployed any more than men have walked
in the moon. Just more pish-posh propaganda
from the government.
Relatively few people, certainly among those under the age of 50, have ever seen a nuclear blast in person. As time goes by, these weapons will seem less like game-changing, world-ending tools of the Apocalypse and more like, well, bigger bombs.
One can wonder, was it disinformation or just that they didn't know good neutron reflectors which could be used for making viable bombs?