Or maybe he's just looking out for his own self interest. The guy is well into his seventies you know .
I don't believe he did suggest the use of nuclear weapons in Afghanistan, it doesn't fit with his foreign policy modus operandi. Lugar is an internationalist in the grandest sense, which is part of the reason why a lot of people think he might show some serious pause before voting for Bolton for UN Ambassador. He's also been one of the sole critics of Bush foreign policy from his own party.