Von Braun was Hitler's secret weapon!
http://www.ag.wastholm.net/message/136Von Braun's relationship to the Nazi Party is complex; although he was not an ardent Nazi, he did hold rank as an SS officer. His relationship to slave labor is likewise complicated, for his distance from direct responsibility for the use of slave labor must be balanced by the fact that he was aware of its use and the conditions under which prisoners labored.17
Atrocities perpetrated at V-2 production facilities at Nordhausen and the nearby concentration camp at Dora-where some 20,000 died as a result of execution, starvation, and disease-stimulated controversy that plagued the rocket pioneers who left Germany after the war. The most important V-2 production sites were the central plants, called Mittelwerk, in the southern Harz Mountains near Nordhausen, where an abandoned gypsum mine provided an underground cavern large enough to house extensive facilities in secrecy. Slave labor from Dora carved out an underground factory in the abandoned mine, which extended a mile into the hillside. Foreign workers under the supervision of skilled German technicians assumed an increasing burden; at Mittelwerk, ninety percent of the 10,000 laborers were non-Germans.18
http://history.msfc.nasa.gov/vonbraun/excerpts.html