An Anxious Peace

By any measure, Hans Mark was a warrior of the Cold War. Born in Mannheim, Germany, in 1929, he spent his early childhood in Vienna before escaping the Nazi Anschluss in 1938 and eventually emigrating to the United States, settling in New York. He graduated from high school in 1947, went west to attend the University of California, Berkeley, and later earned a PhD in physics from MIT. His work in nuclear engineering soon set him on a path that would be shaped by aeronautics, space exploration, a