Sidney Blumenthal gives us the Leader as what I will call a cartoon-like depiction of Narcissistic Personality Disorder
Narcissistic Personality Disorder is considered a serious illness. When it occurs it is (as one might imagine) difficult to treat. Basically you can expect that hardly anyone with NPD will actually cooperate in therapy, so that’s that. It is not a common disorder, like depression or anxiety, so most of us don’t have a lot of personal experience with people suffering from it (though I’ve had an encounter).