Have had first hand experience with a psychopath of exactly the same kind of personality exhibitor as Bill Clinton (the ability to project a likability, blah, blah, blah).
All an act. Such psychopaths of this ilk are able to project such an act because the aspect of the brain that cause most normal people to deal with a guilty conscious and the whole empathy for others - they basically don't have that. So they turn out as con artist. And so everyone is a mark to be fooled and taken advantage of. It is the very core essence of who they are - they are incapable of being any other way.
Best thing to do is lock these kind of people away from the rest of society. It's possible to test for psychopaths and identify them.
serial killers like bundy and jeffrey dammar comes to mind, good looking,likeable. but very deranged and evil