Eighty years ago the United States attacked Japan with an atomic weapon. Three days later, the U.S. used another one. The names of the bombed cities, Hiroshima and Nagasaki, are now synonymous with the devastation of nuclear weapons. Nathaniel Dove spoke to a survivor of one of those bombs, now 93 years old. They discussed what he witnessed and his concerns the world could again be entering an era of fierce nuclear competition.