"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
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.