WILMINGTON, Del. — President-elect Joe Biden made himself scarce on purpose Tuesday, while President Trump denied responsibility for the deadly siege of the U.S. Capitol carried out in his name and set off for a kind of anti-immigration victory romp along the Texas border.

In a bitterly divided nation groping toward Biden’s presidency eight days away, each man was speaking a language his supporters understand.

Biden’s team announced at 9:03 a.m. that he would make no appearances for the day. That was about an hour before Trump launched what might be his last trip as president with a blast of puffery and prevarication.

“We’re going to the southern border. As you know, we’ve completed the wall,” Trump said falsely on the White House lawn, his helicopter whirring behind him. “They may want to expand it. We have the expansion underway. It’s been tremendously successful, far beyond what anyone thought.”

Biden had answered a few questions from reporters Monday, after he got his second dose of the coronavirus vaccine.

He reiterated his hands-off stance to the Democratic-led efforts to force Trump from office in the wake of the mob attack last Wednesday, and he said he is confident he can safely take the oath of office outdoors on Jan. 20. The handover of power will take place at the Capitol, site of the attempted armed insurrection against his election victory.

He is not scheduled to appear in public again until Thursday and Friday, with events focused on his twin plans for the economic and public health responses to the coronavirus pandemic.

The incoming president owes his victory in large part to a pledge to return the country to predictable norms and to apply science and effort to the fight the coronavirus, now raging at a record pace even as Americans begin to get lifesaving vaccines.

“My number-one priority is getting vaccines in people’s arms as rapidly as we can,” Biden said Monday, adding that the current death rate, averaging more than 3,000 Americans per day, is “beyond the pale.”

“It’s just wrong, and we can do a lot to change it,” Biden said, focusing on a subject Trump has all but ignored since Election Day.

Biden seems determined to be the not-Trump, even at the risk of being a bystander to the waning days of the Trump Show. It was the same practice he followed during the campaign, to evident success.

By remaining silent Tuesday, Biden was staying on message, said Victoria DeFrancesco Soto, a political science professor at the University of Texas at Austin.

“He ran on being the adult,” she said. “And what do adults do? They roll up their sleeves and get it done.”

Some Democrats might prefer to see Biden battling Trump point by point, but Biden is hewing to his instinct that more people want to move on, DeFrancesco Soto said.

“If I were Biden, I would save my energy” for legislation on immigration and other issues he has pledged to address in the first 100 days of his term, “as opposed to retorting whatever Trump is saying,” she said.

“That’s a death spiral,” she said. “If you have to respond to every false claim Trump says, you would use up every minute of the day.”

It was perhaps fitting that Trump’s first foray outside the White House since the mob attack would be a visit to the multibillion-dollar border wall project wrought by the “Build that wall” chants he rode to office in 2016.

The wall will now probably never be finished. Biden has vowed not to build another foot of it, and he is under pressure to formally kill off the project with an executive order on his first day in office.

It was also fitting that in some of his first in-person public remarks since he launched violent supporters toward the Capitol with the false assertion that the election had been stolen, Trump tried to deflect blame for the result.

“People thought that what I said was totally appropriate,” Trump said as he was about to board Air Force One. He then pivoted to social justice protests last summer and some of vandalism and violence that took place then.

“And if you look at what other people have said, politicians at a high level, about the riots during the summer, the horrible riots in Portland and Seattle, in various other places,” Trump said. “That was a real problem.”

Besides his assertion about the wall’s completion, Trump also falsely claimed there is a “surge” of illegal immigration, including caravans bent on breaching the border, a claim he also made in 2018. About 450 miles of barrier have been built or rebuilt across a 2,000-mile expanse, the vast majority being a reinforced version of fencing that existed before Trump took office.

Part of the job of president is performative, something Trump always understood on a gut level even when he performed badly. He played the same part Tuesday that he often played as president — part emcee, part folk hero, part victim.

Visiting a section of flag-draped wall near Alamo, Tex., Trump signed his name on a plaque and posed for pictures with Border Patrol agents. Songs from the Trump campaign-rally playlist played as he celebrated, including “YMCA” by the Village People, often the closing number at Trump’s signature political events.

“We worked long and hard to get this done,” Trump said of the wall. “They said it couldn’t be done, and we got it done.”

His speech veered between “Make America Great Again” greatest hits and attempts to address the Capitol assault and the possibility that he may be punished for it in Congress, with asides on the pandemic and the actions taken by major technology companies such as Twitter to mute him.

“Now is the time for our nation to heal, and it’s time for peace and for calm,” Trump said. “Respect for law enforcement and the great people within law enforcement — so many are here — is the foundation of the MAGA agenda,” he said. “We’re a nation of law, and we’re a nation of order.”

Biden aides said Trump’s claims Tuesday are not going unanswered. Vice President-elect Kamala D. Harris said during a Univision interview Tuesday evening that immigration will be “our first order of business.”

Asked about Trump’s assertions that his words before the Capitol attack were “totally appropriate,” Harris scoffed.

“That’s just not true,” Harris said. “It’s simply not true.”

Biden kept mum.

Chelsea Janes in Washington contributed to this report.