Two top political reporters at The New York Times, Maggie Haberman and Jonathan Swan, dug deep into the worst three weeks of Donald Trump’s campaign. Until the day President Biden stepped aside, Trump and his aides thought he was cruising to victory. They spent millions preparing to display Biden’s every gaffe and stumble. The failed assassination attempt in Pennsylvania turned him into a martyr, then the worshipful Republican Convention showed the party completely solidified behind him. His pick for VP, JD Vance, he believed, guaranteed MAGA control of the party far into the future. He was unstoppable, he thought.

But then Biden withdrew from the race and endorsed Kamala Harris. Then JD Vance’s past remarks about “childless cat ladies” surfaced, followed by a furor. Allies urged Trump to replace Vance, but Trump doesn’t admit error.

Trump sneered at Kamala Harris, but she attracted huge crowds. Trump couldn’t understand. He insisted that photos showing her enthusiastic crowds were fake, created by artificial intelligence. He views her with contempt, “dumb,” “low IQ.”

Haberman and Swan wrote:

The Aug. 2 dinner at the Bridgehampton, N.Y., home of Howard Lutnick, the Cantor Fitzgerald chief executive, was a high-powered affair. Among the roughly 130 people who dined under an air-conditioned tent were some of Donald Trump’s wealthiest supporters, including the billionaire hedge-fund financier Bill Ackman, who sat next to the former president, and Omeed Malik, the president of another fund, 1789 Capital.

Some guests hoped Mr. Trump would signal that he was recalibrating after a series of damaging mistakes. He did not.

Before the dinner, answering a question that voiced concerns about the upcoming election during a small round-table discussion inside Mr. Lutnick’s house, Mr. Trump said, “We’ve got to stop the steal,” reviving yet again his false claims about the 2020 election — claims that his advisers have urged him to drop because they don’t help him with swing voters.

According to two people present, Mr. Trump himself also brought up his remark, made two days earlier at a gathering of the National Association of Black Journalists, in which he had questioned Vice President Kamala Harris’s racial identity.

It had been a display of flagrant race-baiting that was egregious even by Mr. Trump’s standards, and it instantly reprogrammed America’s TV news chyrons: He falsely claimed that Ms. Harris had only recently decided to identify as Black for political purposes.

But Mr. Trump showed no regret. “I think I was right,” he told the rattled donors that Friday night.

Later, at dinner under the tent, Harrison LeFrak, the scion of a New York real-estate family, whose father is an old friend of Mr. Trump’s, asked how Mr. Trump planned to take the narrative back from Democrats, and what his positive vision for the country would be. It appeared to be a request for reassurance.

Mr. Trump provided none. Instead, he criticized Ms. Harris on a range of fronts, before adding: “I am who I am.”

Trump is furious that Harris is drawing large, enthusiastic crowds. For the first time, he is facing an opponent who gets more news coverage than he does.

He is beginning to realize that if he wants to win, he has to work for it. Not so easy for a 78-year-old man. He would rather be playing golf.

He is angry. He’s lashing out at people he needs, like Governor Kemp of Georgia. He is focused on re-litigating his loss in 2020.

Last night, he spoke at length with Elon Musk on Twitter. Many who listened responded that he was “slurring” his words. The term “slurring” was trending on the site.

In his anger, he is even more unhinged and bitter than ever.