If I were asked to name the most important date in the history and prehistory of the human race, I would answer without hesitation 6 August 1945. The reason is simple. From the dawn of consciousness until 6 August 1945, man had to live with the prospect of his death as an individual; since the day when the first atomic bomb outshone the sun over Hiroshima, mankind as a whole has had to live with the prospect of its extinction as a species…
as the devices of nuclear warfare become more potent and easier to make, their spreading to young and immature as well as old and arrogant nations becomes inevitable, and global control of their manufacture impracticable. ..One might compare the situation to a gathering of delinquent youths locked in a room full of inflammable material who are given a box of matches – with the pious warning not to use it.
~Arthur Koestler in Janus~