The atomic bombs dropped on Hiroshima and Nagasaki in 1945 permanently altered the world we live in. Fear of nuclear annihilation became a fact of life. Although the end of the Cold War relaxed the tensions somewhat, the combined arsenals of existing nuclear powers are still sufficient to destroy most of life on this planet many times over, and controversies continue over nuclear weapons programs in Iran and North Korea. How did this extraordinary state of affairs come about? Why were the bombs made when and where they were made? Why were they used? Did the individuals involved understand the destructive potential of these new weapons and ponder moral questions involving their manufacture and use? Did they anticipate the nuclear arms race that has resulted? How does this episode fit into the longer history of the relationship between science and warfare? How were both hopes and fears transferred to the debates over nuclear power? Readings will likely include Rhodes, The Making of the Atomic Bomb , Hachiya, Hiroshima Diary , Gordin, Red Cloud at Dawn , and a variety of selections concerning nuclear proliferation, the disarmament movement, and nuclear power.