In 1945, in the final days of the war in Europe, the German rocket engineer Wernher von Braun was interrogated by US and British intelligence officers about the rocket programme he had overseen. Out of it had come the V2 ballistic missiles the Nazis had used to bomb London and Antwerp. The Americans wanted to know how he and his technical team had made this extraordinary weapon, and how he imagined its future development. The longer arc of the story is one of the most extraordinary of the 20th century: despite his past as a high-ranking SS officer, and his...