the atomic bomb

Einstein himself was not the brain behind the making of the first atomic bomb but of course his famous theory of E=mc2 paved the way for it and he himself casually wrote a forwarding letter to the then President of America that atomic bomb is a possibility that can come true if the government of America is determined to get it and America should try to get it to defeat Germany and Japan before they can make any further harm for mankind. But Einstein himself was not aware and nor the scientists who were involved in the famous Manhattan Project were aware that Atom bomb could be so much destructive in nature.