Donald Trump speaks at a campaign event on Wednesday in Charlotte. (Carlo Allegri/Reuters)

George Stephanopoulos interviewed Donald Trump on Wednesday. Straining for evidence to support his unsupportable assertions, Trump looked at times desperate, as though he knew he was spinning his wheels but had nowhere to hide.

Trump cannot admit his own ignorance or bring himself to step back from his embrace of Russian President Vladimir Putin. As to the latter, Stephanopoulos pressed Trump on denying that the Russians are behind the hacking of Democrats. Trump insisted — contrary to the words of the intelligence professionals who briefed him — that we don’t know that it was the Russians. Why disregard the conclusion of the entire intelligence community? Trump knows hacking! (“Well, I haven’t seen the conclusion. But you know what, hacking I understand. And you really — it’s very hard to determine who’s doing the hacking.”) This is the arrogance and the narcissism of Trump: Only he knows the truth; everyone else is a dolt. But when asked for specifics, he becomes incoherent.

At the third and final presidential debate, Democratic presidential nominee Hillary Clinton said Russian President Vladimir Putin would "rather have a puppet as president." (The Washington Post)

Things got worse when the conversation turned to Iraq. Trump recently declared that we shouldn’t have said we would retake Mosul in order to preserve the “element of surprise.” With zero proof, he declared that the operation was a failure. Trump’s comments have been widely mocked, but he can never admit a misstep. “You can tell your military expert that I’ll sit down and I’ll teach him a couple of things,” he proclaimed. Too bad he wasn’t asked whether he has a single fact the generals don’t.

The Clinton campaign put out a statement by one of the many generals endorsing her, which read in part:

Donald Trump’s disrespect for our military knows no bounds. This week, as brave American troops embarked on a crucial mission supporting anti-ISIS forces in Iraq, Trump was already declaring defeat. He called our leaders stupid for not following his uninformed advice. And now he’s personally insulting a military expert and retired Army Colonel who served for 30 years for knocking his ‘plan.’ “A complex operation to take a major city — with hundreds of thousands of civilians, untold traps and IEDs, and the possibility of street-to-street fighting — requires careful planning and methodical execution, not a fly-by-night bum’s rush.

Trump tellingly declared, “I can put my narrative before the American people and let whoever this person is put his, and they will agree with me.” Truth doesn’t matter; he simply can convince the voters of anything. That’s a narcissist’s mental process; only what he thinks and can convince others of matters.

Trump’s ego is dwarfed only by his ignorance. And that’s at the heart of his self-destructive rhetoric, inept campaign, debate blunders and constant gaffes. No one can ever tell him anything, so he lives in his own world, a giant in his own mind. He really has no idea what he’s doing.

His insecurity is palpable. A 70-year-old man feels compelled to say: “Look, I went to an Ivy League school. I was a good student. I’m a very smart person. I — I know what I’m saying.” To quote Hillary Clinton from the final debate, “I mean, who does that?” A man who isn’t that smart and has no idea what he is saying — and a man who is going to be humiliated on the biggest stage ever, losing to a woman he says sleeps all day, Trump will be a loser, maybe a historic one, and — watch and see — he will have the biggest temper tantrum you’ve ever seen. Yuuge.