"The weapon devised as an instrument of major war would end major war. It was hardly a weapon at all, the memorandum Bohr was writing in sweltering Washington emphasized; it was "a far deeper interference with the natural course of events than anything ever before attempted" and it would "completely change all future conditions of warfare." 2025 When nuclear weapons spread to other countries, as they certainly would, no one would be able any longer to win. A spasm of mutual destruction would be possible. But not war."