With the onset World War II in 1939, Europe was further destabilized and Einstein feared that the Nazi regime would be victorious. At the urging of fellow scientist
Leo Szilard https://teakdoor.com/images/smilies1/You_Rock_Emoticon.gif, Einstein wrote a letter to US President Roosevelt warning that the US must develop the atomic bomb before the Germans did. As a result, President Roosevelt initiated a research project to create an atomic bomb, and the Nuclear Age was set in motion. However, as the realization of nuclear weapons drew near, Einstein looked beyond World War II to future problems that such weapons could bring. In December 1944, Einstein wrote to physicist Niels Bohr,
“When the war is over, then there will be in all countries a pursuit of secret war preparations with technological means which will lead inevitably to preventative wars and to destruction even more terrible than the present destruction of life.”