President Trump has reverted to using graphic depictions of violence as a centerpiece of his reelection campaign strategy, using his Twitter account, his stump speech and even the White House podium as platforms for amplifying domestic conflict.

His 2016 focus on radical Islamist terrorism and undocumented-immigrant crime, which he credited with helping him win the Republican nomination, has been replaced by warnings of new threats as he elevates gruesome images of Black-on-White crime, street fights involving his supporters and police-misconduct unrest nationwide.

The pattern continued over the holiday weekend, when he tweeted video of a melee in Texas between protesters and security officers during an event for a Trump-affiliated group and two celebratory videos of a protester in Portland, Ore., with his feet on fire. One of the videos was scored to the Kenny Loggins song “Footloose,” and the second featured mocking play-by-play commentary by a mixed-martial-arts announcer.

“These are the Democrats ‘peaceful protests,’ ” Trump wrote. “Sick!” On Monday, he retweeted a prediction that political unrest “could lead to ‘rise of citizen militias around the country.’ ”

The strategy echoes the approach that fueled his climb in politics as he shocked the political world with graphic warnings about “rapists” crossing the border illegally from Mexico, welcomed the families of crime victims to speak at his events and said he favored instructing the military to target the families of Islamist extremists, a probable war crime. He also repeatedly encouraged assaults on protesters at his events.

In each case, the unprecedented focus on violence by a high-profile American politician allowed Trump to attract attention, turning his rallies into unpredictable and raucous affairs that were widely viewed. It also set the stage for Trump to establish his political persona as a strongman itching to dominate threats foreign and domestic.

Nearly four years after winning that race, Trump is making the same argument, albeit about different dangers, using the specter of violence amid Black Lives Matter protests to claim superior toughness and promising forceful resolution if given the chance.

“These people only know one thing, and that is strength,” he said Wednesday in Wilmington, N.C., of violent street protests in Oregon and Wisconsin. “That’s all they know — strength. And we have strength.”

On Monday, Trump retweeted footage of Black protesters in Pittsburgh screaming at White outdoor diners, drinking from their glasses and knocking over their dishes during a protest over the weekend.

“Disgraceful. Never seen anything like it. Thugs!” Trump wrote. “And because of weak and pathetic Democrat leadership, this thuggery is happening in other Democrat run cities and states. Must shut them down fast.”

Amid a pandemic that has killed more than 186,000 Americans, the jarring political gambit has shifted the focus of the presidential campaign, forcing Trump’s Democratic opponent, former vice president Joe Biden, to air an ad, titled “Be Not Afraid,” focused on his own opposition to the recent violence in Oregon and Wisconsin.

“The president is on offense, and that is always a good thing,” said Roger Stone, a former Trump political adviser who received a presidential commutation after seven felony convictions this summer. “The law-and-order issue really motivates the president’s base, and it also appeals to independents.”

Although Trump has received no big boosts in polling, he unapologetically promoted a video last week of his supporters attacking protesters in Portland, later arguing at the White House that their firing of paintball guns and pepper spray in city streets from the back of pickup trucks was “defensive.” On Twitter, he said the conflict was a logical response to provocation by liberals.

“The big backlash going on in Portland cannot be unexpected,” Trump wrote in a tweet that included a video of the incident.

He also has returned to using his Twitter account to broadcast falsehoods that perpetuate racial conflict. For the third time this summer, on Aug. 30 he retweeted a video of a Black man brutally attacking a White person, this time with a caption falsely suggesting that the assailant in a New York subway assault in 2019 was connected to Black Lives Matter or antifa.

The posts echo a 2015 Trump retweet that showed a picture of a Black man with a gun and falsely claimed that Black people commit a majority of homicides against White people, a racist trope for which he never apologized. The White House argued this month, as Trump did in 2015, that he was not responsible for the accuracy of his retweets.

Politically motivated street fights have become more common during his presidency. Conflicts at protests have led to injuries in recent weeks in places such as Kalamazoo, Mich.; Bloomington, Ind.; and Weatherford, Tex., as protesters of police misconduct have clashed with counterprotesters who are sometimes dressed in Trump-branded apparel and claim to be helping to keep the peace. In one case, a gun-wielding Trump supporter in Kenosha, Wis., was charged with murder after allegedly killing two protesters and injuring a third. (A supporter of a far-right group was fatally shot during a counterprotest by Trump backers in Portland last month. The suspect, a backer of the far-left antifa movement, was killed by law enforcement Thursday.)

In the face of this violence, Trump has condemned the actions of left-wing rioters but declined to condemn violence by his supporters, even as he falsely claims that Biden is refusing to denounce violence on the left.

“I have the tough people, but they don’t play it tough — until they go to a certain point,” Trump said last year in an interview with Breitbart News when asked about fights over free speech on college campuses. “And then it would be very bad, very bad.”

From his start in politics, Trump has brushed aside the idea that he has a responsibility for any violence that results from his campaign style. When a reporter asked in 2015 whether he was concerned that his rhetoric against protesters and immigrants might lead to additional violence in American streets, he recoiled at the question.

“People are getting hurt. People are being decimated by illegal immigrants. The crime is unbelievable,” he said, an argument belied by statistics. “Now in my way, I don’t want anybody hurt. But people are being hurt. So when you ask that question, it’s very unfair.”

His answer was notable for its zero-sum view: Suffering in the country was inevitable — the question was who suffered more.

Trump’s return to focusing on violent threats and conflict follows summer months in which he appeared politically adrift as the coronavirus pandemic overtook the nation, infecting at least 6.2 million people and dampening the economy.

He initially wavered about whether to focus campaign advertising on touting his pandemic response or on attacking his opponent, before eventually launching attacks on Biden’s ties to China, his mental acuity and his policy positions. Biden’s polling advantage widened.

When nationwide protests against police misconduct led to violence this summer, Trump’s strategy shifted again. A July 9 set of talking points distributed around the White House by Stephen Miller, an adviser who wrote Trump’s 2016 nomination speech, previewed the message that Trump would settle on for the final push to the Republican National Convention.

The solution Miller described, which Trump soon incorporated into his rhetoric and advertising, was to portray Biden as a fundamental threat to public safety. “No one will be safe in Joe Biden’s America,” the document read. The Democratic nominee, Miller’s document continued, “will surrender America and its citizens to the violent left-wing mob” and “abolish the American Way of Life.”

The shift sought to rehabilitate Trump’s political message of dominance and turn the discussion away from the pandemic, which public polling showed had become a drag on the president’s support.

“You can’t really tell people that there is no covid crisis, because they are surrounded by it. The only thing you can do is make something else louder,” said Matthew Baum, a political scientist at Harvard University who studies political persuasion and misinformation. “You don’t have to persuade people. All you have to do is say: ‘Don’t look over there. Look over here.’ ”

Biden has argued that Trump is trying to distract Americans from his inability to better address the health, economic and race-relations crises facing the nation.

Trump’s message is, “ ‘The whole country is up in flames. Everything is burning. Law and order,’ ” Biden said Friday at a news conference in Wilmington, Del., “because he doesn’t want to talk about anything, anything at all, about the job he hasn’t done.”

Biden has mocked Trump’s effort to cast him as responsible for any street violence, no matter the alleged perpetrator.

“Ask yourself: Do I look like a radical socialist with a soft spot for rioters? Really?” Biden asked during a speech on Aug. 31 in Pittsburgh. “I want a safe America — safe from covid, safe from crime and looting, safe from racially motivated violence, safe from bad cops. Let me be crystal clear — safe from four more years of Donald Trump.”

Tim Murtaugh, a spokesman for the Trump campaign, said the president is focused on helping communities affected by the violence. “These riots are destroying the life’s work of Black, Hispanic and Asian business owners, and they have to stop,” he said.

Expressions advocating violence were central to Trump’s early political endeavors.

“I’d like to punch him in the face, I’ll tell you,” Trump said about a protester at an event in Las Vegas. When a nonviolent Black protester was beaten at a rally in Birmingham, Ala., by a White crowd, Trump responded the next day, “Maybe he should have been roughed up.”

He argued repeatedly at rallies for the extrajudicial abuse or even killing of Army Sgt. Bowe Bergdahl, who had left his post in Afghanistan. “Thirty years ago, he would have been shot,” Trump said. At another event, he said of Bergdahl’s capture by the Taliban, “They beat the crap out of him, which is fine.”

Rather than recoil, his crowds embraced the tough talk, and Trump has delivered more as president. After Greg Gianforte, then a Montana congressional candidate, physically attacked a reporter in 2017, Trump turned the incident into an applause line. “Any guy that can do a body slam, he is my type!” the president said.

When Trump addressed a law enforcement group in 2017 on Long Island he urged incaution in policing.

“When you see these thugs being thrown into the back of a paddy wagon,” he said, “you just see them thrown in, rough. I said, ‘Please don’t be too nice.’ ”

The new threat Trump has focused on is depicted as no less ominous than his previous targets — and it is similarly inflated with rhetoric that mixes descriptions of actual events with conspiracy theories for which he offers no evidence. In recent days, he has described “rioters, anarchists, agitators and looters” who he claimed in a Fox News interview, without evidence, have been traveling the country in commercial planes to create havoc, funded by “people you have never heard of” who operate in “dark shadows.”

He also has tried to adjust the historical record by claiming federal actions he instigated have proved that his solution of physical toughness and law enforcement domination is responsible for clearing streets of violent protesters. On a visit to Kenosha, he claimed that his push to deploy the National Guard saved the city from further rioting after the police shooting of Jacob Blake, an unarmed Black man.

“If I didn’t INSIST on having the National Guard activate and go into Kenosha, Wisconsin, there would be no Kenosha right now,” Trump tweeted last week. Federal officials did work with local law enforcement in quelling the protests, but Wisconsin Gov. Tony Evers (D) had ordered the Guard to the city a day before Trump’s public call for their deployment.

Pollsters have noted a shift in polling around the Black Lives Matter movement, which was initially broad and bipartisan in the wake of the killing of George Floyd in Minneapolis police custody in May. Support for the movement in Wisconsin, according to a Marquette University Law School poll, fell from 59 percent to 49 percent between June and August.

But national polls continue to show that Biden leads Trump on questions of which candidate would make the country safer. A recent national Quinnipiac University poll found that 50 percent of likely voters said Trump made them feel less safe, compared with 35 percent who said he made them feel more safe.

By contrast, 42 percent of voters said Biden would make them feel more safe as president, compared with 40 percent who said they would feel less safe.