As WW2 wound to a close and the Allies moved into Germany, the Allies discovered that the Nazis were years ahead of them in many key technology areas. The Nazis were experimenting with supersonic aircraft, had made new discoveries in industrial chemistry (including the production of nerve gasses), and had developed high-precision machining techniques better than anything the West could claim. Of course, the Germans were also working on advanced rocketry/misssle technologies and had developed a huge resevoir of knowledge regarding human performance under adverse flight conditions.
Japan had not yet fallen and the Cold War was beginning to take shape so there was some urgency to the matter. The Allies and the West wanted these technologies; first, to beat Japen, and next, to keep the information out of the hands of the Soviet Union.
This is the story of Operation Paperclip; the program to bring Nazi scientists to the West to integrate them and their technologies.
Obviously, there are HUGE moral questions here; which the government tended to ignore as time went on and as the Soviets became more of a threat. Do you want to the enemy to get scientists who know how to make industrial quantities of nerve gas? The human performance data was gathered by essentially torturing prisoners to death. Do you use the data? Do you allow the data to fall into the hands of your enemies, who will probably use it against you? What about the scientists themselves? What did they know ahout the Holocaust and their part in it?
The book does make some judgements (and is especially harsh of Werner Von Braun) but, for the most part, the author tries to paint an accurate picture of the situation and the thinking of the players.