PITTSBURGH (NewsNation) — The battle over who can keep Americans safe after recent deadly protests emerged Monday as the sharpest dividing line for the presidential campaign’s final weeks as Joe Biden condemned the violence and President Donald Trump defended a supporter accused of fatally shooting two men.

While the president blamed Biden, his Democratic rival, for siding with “anarchists,” Biden, in his most direct attacks yet, accused Trump of causing the divisions that have ignited the violence. He delivered a speech distancing himself from radical forces involved in altercations.

“He doesn’t want to shed light, he wants to generate heat, and he’s stoking violence in our cities,” Biden said Monday. “He can’t stop the violence because for years he’s fomented it.”

Biden’s remarks in Pittsburgh come as Trump accused Democrats of losing control of sometimes violent demonstrations over police brutality and racial inequality that have gripped American cities for months.

Trump blames radical troublemakers stirred up and backed by Biden. But when he was asked about one of his own supporters who was charged with killing two men during the mayhem in Kenosha, Wisconsin, he declined to denounce the killings and suggested that 17-year-old Kyle Rittenhouse was acting in self defense.

After a confrontation in which he shot one man, police say, Rittenhouse was chased by two others. The teenager, who was illegally carrying the firearm, was charged with homicide after killing two people and injuring a third.

“That was an interesting situation,” said Trump. “He was trying to get away from them, I guess, it looks like, and he fell. And then they very violently attacked him. … He was in very big trouble. He would have been — you probably would’ve been killed.”

Trump’s refusal to condemn the shootings could add to tensions and the reaction in Kenosha when he visits on Tuesday. He’s going despite pleas from Wisconsin’s Democratic governor to stay away for fears of sparking further tumult.

Trump said his appearance could “increase enthusiasm” in Wisconsin, which is a battleground state in the presidential race.

Biden saw Trump’s impact far differently, accusing the president of “poisoning” the nation’s values.

In Pittsburgh, the former vice president also tried to refocus the race on what has been its defining theme — Trump’s handling of the COVID-19 pandemic that has left more than 180,000 Americans dead — after a multi-day onslaught by the president’s team to make the campaign about the violence rattling American cities.

Biden himself has largely remained near his home in Delaware to prevent the spread of the coronavirus, but he stepped out in a new phase of his campaign on Monday, in a speech in Pittsburgh and a brief stop at a local firehouse.

Trump and his campaign team believe that the more the national discourse is about anything other than the virus, the better it is for the president. They have seized upon the recent unrest in Portland and Kenosha, leaning hard into a defense of law and order while suggesting that Biden is powerless to stop extremists.

Biden rejected the charge, firmly decrying the clashes.

Set aside on Monday were his appeals about the “soul of the nation,” a staple of his usual stump speech, replaced by an urgent call for action and and his fierce accusation that Trump was a “toxic presence in this nation for four years” who was “poisoning the values this nation has always held dear, poisoning our very democracy.”

The president and his team continued to hammer away on what they believe is a powerful electoral argument, contending that Biden is in thrall to leftist forces and emphasizing chaotic protest images they believe could send worried suburban and senior voters back to Trump’s column.

“Just watched what Biden had to say,” Trump tweeted soon after the former vice president concluded his remarks in Pittsburgh. “To me, he’s blaming the Police far more than he’s blaming the Rioters, Anarchists, Agitators, and Looters, which he could never blame or he would lose the Radical Left Bernie supports!”

Biden has been pushed by worried Democrats — including some voices inside his own campaign — to deal with the violence head on and at greater length, though he had previously condemned it. With Trump pounding the issue in his convention speech, which was then followed by more bloodshed over the weekend, many in Biden’s party, still shell-shocked by 2016, urged the former vice president to get ahead of the rare issue that has broken through the national focus on the pandemic.

But Biden didn’t just play defense, he went on the attack, saying Trump not just as inciting violence but for his ties to Russia and his handling of the nation’s economy.

Following up his Democratic convention address, in which he didn’t mention Trump’s name, Biden on Monday invoked Trump’s name 32 times, directly assailing the president in remarks that seemed intended to silence worries in his party and the Beltway’s chattering class. He pulled no punches about the violence.

“It’s lawlessness, plain and simple. And those who do it should be prosecuted,” Biden said.

He also accused Trump of being too “weak” to call on his own supporters to stop acting as “armed militia.” And he leaned on his own 47-year career in politics to defend himself against Republican attacks.

“You know me. You know my heart. You know my story, my family’s story. Ask yourself: Do I look like a radical socialist with a soft spot for rioters? Really?”

He declared that that even as Trump is “trying to scare America,” what’s really causing the nation’s fear is Trump’s own failures. He pointed to a rise in murders this past year, the 180,000 dead Americans from the coronavirus and the economic damage done by the pandemic.

“You want to talk about fear? They’re afraid they’re going to get COVID, they’re afraid they’re going to get sick and die,” Biden said.

In Kenosha, Wisconsin, the National Guard has been deployed to quell demonstrations in response to the police shooting of Jacob Blake, a Black man, that have resulted in some looting, vandalism and the shooting deaths of two protesters. And this weekend, one of Trump’s supporters was shot at a demonstration in Portland, Oregon, prompting multiple tweets from Trump.

The former vice president’s speech Monday appeared to jump-start the general election campaign a week ahead of its normal Labor Day kickoff, as both Biden and his running mate, Kamala Harris, will begin venturing out despite the pandemic. Biden, who may make his own visit to Wisconsin this week, has missed the glad-handing of a traditional campaign and managed to have a brief moment of retail politics when he delivered pizzas to Pittsburgh firefighters.

The setting for Biden’s speech was no accident: Pennsylvania, his native state, is a vital battleground with both candidates competing for its working class voters. Trump, whose campaign is focusing on the state’s rural counties, eked out a 44,000-vote win in 2016 but Biden, who is running strong in the Pittsburgh and Philadelphia suburbs.