The way I know he actually believes these things is because this is how actual narcissists I know behave. So I have a point of comparison. I recognize the patterns, which extend past just these statements, including: gaslighting, blame shifting, victim blaming, self victimization, inability to accept any blame whatsoever, the inability to admit he's wrong, etc. This goes faaaaar beyond the typical pandering you get with politicians. It's pathological.

Look at it this way, even politicians who pander are able to exhibit some semblance of humility and self awareness. You'll be able to find exactly 0 instances from Trump admitting he's wrong about anything. In fact, he once said (to Jimmy Fallon) that he has never had to apologize because he's never done anything wrong.

It's narcissism just the same. In fact, that "project a grandiose image that leads to popularity and success" thing is pretty much the crux of it.