History and ethics of working on nuclear weapons

Two currents ran through U.S. scientists' participation in the Manhattan Project. The motive for those who built the bomb was what led Einstein to write President Roosevelt: a Nazi atomic monopoly could mean nuclear blackmail at Hitler's hands. U.S. possession of the dreadful instrument could enable the United States and Britain to avoid that fate. The other current was represented by Vannevar Bush, who persuaded FDR to create the National Defense Research Council and put him in charge. He wanted civilian scientists to help develop new weapons not just to win the war. He believed that "the world is probably going to be ruled by those who know how, in the fullest sense, to apply science." He wanted to be the scientist who oversaw the process of putting the U.S. in that position. The use of atomic weapons was part of that current. By the end of 1944, it was clear that Germany did not have a viable bomb project. The deterrence job was done. But the project was accelerated; the target was Japan. In fact, Germany was explicitly de-targeted much before, on May 5, 1943, by the Military Policy Committee, headed by Bush. He made sure that the scientists who were busy making the bomb were excluded from that decision. Reflecting on it in 1981, Richard Feynman, who was at Los Alamos, opined that he "immorally" failed to reconsider his participation when the Nazis surrendered in May 1945. "I simply didn't think, okay?" he said in explanation. The process had created a U.S. atomic monopoly. Secretary of War Stimson told the newly installed President Truman on April 25, 1945, that the bomb could wreak total destruction. On the other hand, figuring out "the proper use of this weapon" would give the United States "the opportunity to bring the world into a pattern in which the peace of the world and our civilization can be saved." Atomic-tipped global control by the United States with a nuclear monopoly was not what Einstein had in mind. Toward the end of his life, he called writing the letter his "one great mistake." Eight decades later, we are still at the edge of the nuclear precipice. It is essential to reflect on Feynman's self-described thoughtlessness and Einstein's postwar regrets. What might it mean for scientists participating in the production of nuclear weapons today, when there are nine nuclear powers and we are still at the edge of the nuclear cliff?