Northrop was developing "flying wing" aircraft in the 1930s, and the YB-35 flew on June 25, 1946. Germany also worked on similar aircraft in that period, but to imply that later US development of "flying wing" planes stemmed from Nazi research is contrary to fact. Yes, the control of such craft is more difficult, but no, it does not really need high speed computers - control systems just don't need to be fast and complicated just because it's a flying wing.
Some modern high speed aircraft use computer control because the aerodynamic configuration that gives the highest performance is inherently badly unstable.
Over the years, there has been debate about the morality of using the results of vicious Nazi human experiments, mostly in the realm of psychology, I guess that's another of Hitler's toys.