The setting for this piece had several rather special dimensions. First, the Pugwash conference at which the essay was delivered took place in Moscow after the U.S. elections of 1960, before John Kennedy’s inauguration. I was asked to attend by both the outgoing administration and Kennedy because the USSR’s delegation, which was typically made up of physical scientists, included the director of the Institute of World Economics and Politics. Jerome Wiesner and I, associated in the media with the incoming administration, were greeted by Soviet officials as “guerrilla fighters for Kennedy.”