They will do or say anything to win, even if it is not in their best interest.
They take contradictory positions, sometimes within the same sentence. This creates the absurdity of a negotiator dealing with a sociopath being damned if he does and damned if he doesn't.
They do not have a conscience so they lie endlessly and effortlessly.
Obama admitted yesterday he will not budge, even if it destroys his presidency.
There were several leaders who thought they had agreements with Hitler, only to find themselves being bombed by the Luftwaffe shortly thereafter.
Good analysis.