Malignant narcissism is a theoretical personality disorder construct conceptually distinguished from typical narcissistic personality disorder (NPD) by the presence of antisocial behavior, egosyntonic sadism, and a paranoid orientation...

DT is mentally ill. He meets the criteria for Antisocial and Narcissistic Personality Disorders. And based on public conduct, I have no doubt that an evaluation would put him way up on the Psychopathy Checklist.

Lying and "distorting reality" are hallmarks. He breaks every rule in the book in pursuit of his own ends. He lies and distorts reality to rationalize and justify his wrongful conduct. To puff up his over-inflated ego he stereotypes and denigrates those he sees as out-groups. His callous disregard for others and sense of entitlement appear to know no bounds. He weaves grandiose tales of his fearsome power, omnipotence, and unequaled brilliance. He is proudly abrasive and offensive. He clearly enjoys humiliating and embarrassing others, but reacts to any perceived slight to his own person, appearance, or accomplishments aggressively and vindictively.

I'm sure there have been U.S. presidential candidates, and presidents, who could be diagnosed with a personality disorder of some sort, but I can't think any of who exhibited this level of psychopathy. I can't think of any who met as many diagnostic criteria for Antisocial Personality Disorder, or who met as many criteria for Narcissistic Personality Disorder.
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