He’s based mostly on Edward Teller, progenitor of the H-bomb, with a good dollop of Werner Von Braun thrown in for flavor.
Edward Teller wasn't even a German and he never worked for the Nazis. Unlike Werner von Braun.
It is possible to combine the substance of one character with the flavor of another. Edward Teller was a kind of "rationally mad" guy, and political, while von Braun was more of an ethically flexible engineer ("just let me build rockets") and, of course, German.
Edward Teller wasn't 'rationally mad', it was von Neumann who was very eager to drop atomic bombs on the Soviet Union. Besides picturing Edward Teller who actually came from a Jewish family and fled Germany when the Nazis came to power as a devout Nazi is not funny and doesn't even make any sense.
> just let me build rockets
Once ze rockets are up, who cares where zey come down…