I have no idea whether this Twitter exchange had anything to do with Donald Trump revoking former CIA Director John Brennan’s security clearance …

But I wouldn’t be surprised if there is some linkage.

The president has exhibited a shameful display of petulance and idiotic pique at a man whose expertise on vital national security matters he has just tossed into the crapper.

And I have to ask: Why in the world would the president do this?

Oh, I know. It’s because he is a thin-skinned narcissist with delusions of grandeur/godhood.

Brennan’s tweet speaks to the equally idiotic language he used to dismiss Omarosa Manigault Newman, the former White House aide who chief of staff John Kelly fired.

Don’t misunderstand me here. I do not trust Newman, either. However, the presidency used to demand that its occupant demonstrate some level of dignity, decorum and “probity,” a term that Brennan used.

Whatever her beef with the president — or his with her — she didn’t deserve to be talked about in that tone by the head of state of the world’s greatest nation.

And this circles back — every single time — to the issue of whether Donald Trump is morally or intellectually fit to hold the office to which he was elected.

He is unfit at every level imaginable.

Brennan has been denied a security clearance. That, by itself, is a shame. The good news is that Trump’s petulance won’t silence this erudite critic.