Narcissistic personality disorder isn't sufficient to explain Trump. He is overflowing with self pity and is incapable of understanding how his actions have influenced his current lack of popularity. He is lacking in the most basic intellectual skills. He should also have at least a slight understanding of the dangers of surrounding yourself with yes people.
He sounds like a five-year-old surrounded by a highly dysfunctional family. It’s part of his personal psycho-pathology, but in fact he quickly discovered in 2016 that it is very appealing to a significant portion of the population who hold forth the entitlement of a pampered five-year-old.