We scientists have delivered the power into your hands. It is the power to destroy yourselves. What you do with it — whether you rise to the level of your own peril — is no longer a question for physics.
It is a question for the human soul.
The atom has changed everything, save our mode of thinking. And thus we drift toward unparalleled catastrophe. albert einstein the menace of mass destruction full speech
By Albert Einstein (May 31, 1946)
When I first sent my letter to President Roosevelt in 1939, I did so out of the deepest fear that Nazi Germany would succeed in building an atomic bomb. We had reason to believe their scientists were capable of such a horror. I acted to prevent a nightmare. We scientists have delivered the power into your hands