He hasn’t taken office yet, but Donald Trump is lost, wandering in a labyrinth of lies and trying to drag the country in with him.

Witness his reaction to being called out on Sunday by Meryl Streep. Speaking at the Golden Globes, she said she had been stunned and heartbroken to see him mock a reporter with a physical disability.

It happened at a speech in 2015 in South Carolina. Mr. Trump’s target was Serge Kovaleski, of The Times, who has arthrogryposis, a condition that leaves his right arm and hand bent and rigid. “You ought to see this guy,” Mr. Trump told his audience, flailing his own right arm and hand in the air, making spastic movements, disgracing himself. The act was contemptible, and in a way unbelievable: a future president showing the maturity and schoolyard viciousness of an 8-year-old.

“I still can’t get it out of my head,” Ms. Streep said, “because it wasn’t in a movie. It was real life. And this instinct to humiliate, when it’s modeled by someone in the public platform, by someone powerful, it filters down into everybody’s life, because it kinda gives permission for other people to do the same thing. Disrespect invites disrespect, violence incites violence. And when the powerful use their position to bully others, we all lose.”

In early morning tweets, Mr. Trump attacked Ms. Streep and swore innocence:

‘Hillary flunky who lost big. For the 100th time, I never “mocked” a disabled reporter (would never do that) but simply showed him……. "groveling" when he totally changed a 16 year old story that he had written in order to make me look bad. Just more very dishonest media!’

Just more lies upon lies. It all goes back to Mr. Trump’s baseless claim that he saw Muslims dancing in the streets by the thousands after the towers fell on 9/11. Challenged over this, Mr. Trump seized on a 2001 article in The Washington Post, written by Mr. Kovaleski when he was a reporter there, that he said backed up his story. But the article did not do that. It merely reported that the authorities had questioned “a number of people” who were “allegedly seen” celebrating the attack. Nothing has ever come of that “allegedly” — there has never been any evidence to substantiate Mr. Trump’s claim, not then, not now. Mr. Kovaleski did not change his story — not “totally,” not at all. And he did not grovel.