it's a disgrace that he got to live a full life after the war
Agreed. It's even more of a disgrace that he became a celebrity, and was head of NASA in a time where black people and suspected communists would have never been allowed to rise higher in rank than a Nazi.
Using him should've been a secret held in shame, but they paraded this guy around and let him do stuff. At the very least he shouldn't be a household name. Extradite him to be tried after using him to make rockets. Or just life in jail. Or never use him at all and send him to jail. So many better options.