A cheerful Trump, fresh from the debate, rallies in Virginia

The day after a presidential debate that focused on his opponent’s missteps, former President Donald J. Trump returned to the campaign trail Friday afternoon, clearly elated as he walked onto a stage in front of thousands of people on a Virginia field and showed off his performance.

Fresh from a debate in which his attacks, falsehoods and exaggerations went largely unchecked in light of a faltering performance by President Biden, Mr. Trump used the meeting to amplify now-familiar arguments that Mr. Biden was unfit to hold office.

“The question every voter should be asking themselves today is not whether Joe Biden can survive a 90-minute debate performance,” Mr. Trump said, “but whether America can survive four more years of a corrupt Joe Biden in the White House.”

Based on reports that Democrats panicking about the debate were eager to push Mr. Biden off the ticket, Mr. Trump argued that Democrats had no better candidates than his opponent, with whom he has had a long-standing animosity and whom he says he will confidently defeat despite losing to him in 2020.

And Mr. Trump seemed equally buoyed by Friday’s Supreme Court decision that federal prosecutors abused an obstruction law to prosecute some of his supporters who stormed the Capitol on Jan. 6, 2021, in an effort to overturn Mr. Biden’s victory and retain Mr. Trump. .Trump in the White House.

For Mr. Trump, the court’s decision — facilitated in part, he insisted, by the judges he appointed — lent credence to his frequent insistence that his supporters who marched on the Capitol, some of whom turned to violence, were engaged in a political protest and were now being wrongly prosecuted solely because they supported him over Mr. Biden.

Trump told the crowd before him, which had gathered in the summer heat in Chesapeake, Virginia, that the court had decided that Biden’s “branch of injustice wrongfully prosecuted hundreds of Americans for their peaceful protest on January 6.”

The comment drew one of the most energetic cheers from the audience during Trump’s 90-minute speech. Then his supporters began chanting in unison: “USA”

Mr. Trump had spent less time in recent weeks talking about his views on Jan. 6, especially as he campaigned in cities like Philadelphia and Detroit, where he courted black voters. After the debate, he made another attempt to expand his coalition, saying, “Whether you are Democrat or Republican, young or old, black, brown or white, we welcome you to our movement.”

Mr. Trump, who has a history of racist remarks, continued his efforts to win over black and Hispanic voters by claiming, without providing evidence, that the influx of migrants crossing the border illegally was taking “black jobs.” And as he tries to win over union members in key swing states, Mr. Trump appeared to openly court the president of the Teamsters union, Sean O’Brien, whom Mr. Trump invited to speak at the Republican National Convention next month.

“I don’t want to throw names around,” Mr. Trump said after naming Mr. O’Brien, “but he’s a good man.”

But with the debate behind him, Trump has revived strong language that he had only slightly dialed back in recent weeks, including his false claims of widespread 2020 election fraud and his portrayal of Mr. Biden as mentally unfit to lead the country to control.

Mr. Trump has been sharply critical of Mr. Biden’s leadership, repeatedly undermining his debate performance and using it as evidence that four more years of a Biden administration would take the country in the wrong direction. And standing in Virginia, which hasn’t voted for a Republican president since 2004 but which Mr. Trump hopes to turn around, he argued that Mr. Biden’s poor debate performance was a reason to oust Democrats from power on the ballot.

“We don’t just have to fire Biden,” Trump said, as Virginia’s Republican governor, Glenn Youngkin, looked on. “As you saw yesterday, the entire Democratic Party has to be voted out of office.”

Mr. Trump argued that he would be “very happy” if Vice President Kamala Harris somehow became the nominee because he performed better against her. And he joked insultingly that Mr. Biden was wise to pick her because no one wanted Ms. Harris to be president, an attack his campaign made in an ad that aired during the debate.

At times, Mr. Trump — who during the debate agreed to accept the outcome of the 2024 election only if he deemed it fair — appeared to act as if the presidential race had been concluded. He repeatedly referred to a “transition period,” an apparent reference to the post-election period but which he expanded to include the months leading up to the election.

“We have a five-month transition period and I want our enemies to know not to play with us.”

Still, Trump reiterated his claim that America was more threatened by “the enemy within” – a reference to his political opponents – than by foreign powers like China, Russia and North Korea, which he said are “not really enemies if you have a smart president.”

Mr. Trump repeated some of the false claims he made during Thursday’s debate, again accusing Democrats of supporting abortions until “a baby is born.” No state has passed laws that would allow that, and Mr. Biden did not support it during the debate.

And he argued again that Mr Biden had allowed a wave of migrants across the US border with Mexico, which in turn had caused a wave of violent crime. Available statistics show that violent crime has declined, and there is no evidence of a spike in crime caused by migrants.

Trump’s supporters waited in line for hours in the heat to hear him speak. At least three people required medical attention as they waited for the former president to arrive.

Still, the mood seemed buoyant. Before Mr. Trump arrived, several speakers — largely a parade of Republicans who occupied the Virginia governor’s mansion at various points — asked the audience who they thought had won the debate.

Unsurprisingly, the resounding answer every time was “Trump.”