"We have made a thing, a most terrible weapon that has altered abruptly and profoundly the nature of the world . . . a thing that by all the standards of the world we grew up in is an evil thing."

I reviewed the Bird & Sherwin biography of J. Robert Oppenheimer in 2005:
https://www.washingtonpost.com/archive/entertainment/books/2005/04/10/fallout/cf4054f0-92d1-4d59-bf13-0b0701dcdf12/

#Oppenheimer

Fallout

Washington Post
@JamesGleick Worth re-reading: James Cameron’s 1946 article describing witnessing a Bikini Atoll test…. https://arjun.im/post/70266958376/james-camerons-article-on-the-bikini-atoll
James Cameron’s Article on the Bikini Atoll... | IAMARJUN™

James Cameron’s Article on the Bikini Atoll Nuclear Tests The Daily Express July 1, 1946 So we came to Bikini, a typical Pacific corol atoll. Several tiny islands surrounding a lagoon 20 miles long by 10 miles wide. The main island, drawing close on the starboard bow, was so precisely the conventional picture of a South Sea Island that it might have been the jacket of a very old novel. Inside the lagoon as far as one could see were the 73 target vessels disposed in an intricate pattern to achieve every degree of damage. An enormous naval condemned cell. In the centre, standing out amongst the warship grey like a bloodspot on a monk’s robe, was the Battleship “Nevada”, painted from masthead to waterline in a hard hot red. She was dressed in this brutal colour to make her a clear and vivid mark on the lagoon. She was the Bullseye. Aboard the “Nevada” it was like some great forlorn house just before moving day. Here, however, as the tenants moved out the luggage moved in. All over the red docks lay the secondary sacrifices. A 30 ton tank, a heavy field gun, rows of the newest and smartest automatic weapons, delicate electrical and photographic gear, an aircraft or two. Down on the boat deck, under tarpaulin awnings stretched from an aircraft wing, waiting the little company of flesh and blood, standing reflectively in pens for their most abrupt and instructive dissolution. There were a few goats with pale and cynical eyes; one or two brown spotted pigs. A scientist beside me said: “I feel a little like apologising to those pigs, they belong to a reasonable and uncomplicated people, not without a certain grace, at least” he said “They arn’t crazy”. The loudspeaker said “Bomb Gone, Bomb Gone, Bomb Gone!”. I had on my goggle mask, so black and deep it was like staring into velvet. Behind that opacity all things vanished. Sea and ships and sunlight. At the bomb aimer’s words I began to count. When my counting had reached 55 the bomb went off. In that first fine edge of a second it might have been a southern star low down on the horizon. Then it grew and swelled and became brighter and brighter. It pierced the goggles and struck the eye as a crucible does, and in that moment it was beyond every doubt there ever was, an Atom Bomb and nothing else. It was a spheroid, then an uprising wavering thing like a half filled balloon, then a climbing unsteady dome like a mosque in a dream. It looked as though it were throbbing. I tore off my goggles and the globe became a column, still rising, a gentle peach colour against the sky, and from 18 miles I could see a curtain of water settling like rain back into the lagoon. Somehow I found it impossible to believe that the thing produced a hundred million centigrade degrees of heat, ten times that of the surface of the sun. Yet it was beautiful in its monstrous way, a writhing lovely mass. Then, just as I remembered the sound of the explosion, it finished its journey and arrived. It was not a bang, it was a rumble, not overloud, but it thudded into all the corners of the morning like a great door slammed in the deepest hollows of the sea. Beside me a heavy wire stay unexpectedly quivered, like a cello string, for a moment then stopped. Now, standing up unsteadily from the sea, was the famous mushroom. In seven minutes and fifteen seconds our ship’s trigonometry gave it 23000 feet in height and 11600 feet in diameter. From behind me I heard a frantic ticking of typewriters. Very soon I found I was fumbling with my own. The reportage had begun. Many of us will never live it down.

IAMARJUN™

@JamesGleick
I remember when the government was contemplating making a neutron bomb. It wouldn't blow things apart, but release a blast of neutrons that would kill life over a significant area. The idea was to have a deterrent to Soviet armor superiority in Europe.

There was fear they'd actually build it, and then other nations or possibly terrorists would copy it.

I thought at the time the knowledge was the danger, not the device itself.