Ummm....well, technically, we did bring in a bunch of rocket scientists that absolutely were Nazis. Also brought in a bunch to the old OSS which became the CIA. Only hundreds, not thousands, but we did do it. It was decided at the very top it was necessary. The spies had tons of material on the Soviets, the scientists helped with our rocket and nuclear programs.
The first reviews of them showed that many (not all) were died in the wool Nazies. So, they scuttled the reports and greensheeted them (declared that the reviews had determined they were NOT Nazies). But - they were. This is not even a secret anymore - a lot of the paperwork was declassified in the 90's because it was so long ago.
I've heard of that... Project Paperclip... we wouldn't have had our rockets without those guys giving us a kick start. But, I was under the impression that none were actually nazi's. I know that Von Braun was working under the Hitler regime to create liquid fueled rockets, but he never professed any nazi views in the recordings and articles I reviewed on the subject...if you have others, I'm happy to receive the reference.