Friedman was employed for 14 years as a nuclear physicist for such companies as General Electric (1956???1959), Aerojet General Nucleonics (1959???1963), General Motors (1963???1966), Westinghouse (1966???1968), TRW Systems (1969???1970), and McDonnell Douglas, where he worked on advanced, classified programs on nuclear aircraft, fission and fusion rockets, and compact nuclear power plants for spa