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LATROBE, Pennsylvania—President Donald Trump has long signaled that if he loses reelection, it would surely be illegitimate. With his base primed to believe that victory is the only acceptable outcome, the post-election period could be the most combustible in memory. This wrenching summer—and the Trump rally I attended here yesterday—provides a grim preview of what the weeks after the November 3 vote could look like, with a subset of Trump’s supporters already showing that they’re prepared to advance his interests in the streets.

When I asked Leo Walker, a 68-year-old retiree at the rally, whether the president’s backers would publicly protest a Biden victory, he said, “They’ll do more than that. They will take the country back.” By force? “They will take the country back. There’s no doubt in my mind.” Trump, Walker said, “can do no wrong.”

The weeks after the election could be “a very dangerous period” for the country, says Miles Taylor, a former senior official in the Homeland Security Department, whose agents were deployed to quell recent police-violence protests in Portland, Oregon, against the wishes of the state’s leadership. Taylor left the agency last year and has since emerged as an outspoken critic of the president. “I talk to law-enforcement officials all the time who I used to serve with, and they’re nervous about November and December,” he continued. “We’re seeing an historic spike in gun sales. There’s some of the worst polarization in United States history. This is beyond a powder keg. This is the Titanic with powder kegs filled all the way to the hull.”

Faced with civil unrest, a president’s job at the most basic level is to calm things down. That’s not Trump’s style. He’s called the Black Lives Matter movement a “Marxist group,” ignoring its role in fighting racism. He defended 17-year-old Kyle Rittenhouse after he was charged with killing two people during demonstrations in Kenosha, Wisconsin, last week. On the opening night of their presidential-nominating convention, Republicans gave a speaking role to Patricia and Mark McCloskey, the wealthy white homeowners who pointed guns at Black Lives Matter protesters who marched past their St. Louis property. On Twitter, Trump cheered the arrival of his supporters who showed up in Portland to counter prolonged protests there.

The president has also stoked confrontation beyond the demonstrations over police violence and systemic racism. In the spring, he tweeted a demand to “liberate” Michigan, Virginia, and Minnesota, three states with Democratic governors who’d imposed measures aimed at curbing the spread of the coronavirus. Armed protesters showed up at Michigan’s state capitol in May objecting to Governor Gretchen Whitmer’s stay-at-home orders. They’ve also turned up in Texas to defend businesses that have opened in spite of the orders.

“It’s absolutely terrifying,” says Rosa Brooks, a former Pentagon official in the Obama administration who’s been running war-games-style exercises about the election outcome. “People who study political violence have been warning for a long time that conditions that we’re seeing in the United States resemble those that you see in countries that slide all the way down into civil conflict. We’re only going further down that chute.”

Should the election drag on or should their candidate lose, Trump’s most aggressive supporters might consider it a patriotic act to publicly contest what they see as a fraudulent election. That’s one scenario Brooks has been weighing through her work with the Transition Integrity Project, which includes dozens of former government officials and political strategists from both parties. After holding exercises to game out a potential post-election crisis, one conclusion the group reached was that “President Trump and his more fervent supporters have every incentive to try to turn peaceful pro-Biden (or anti-Trump) protests violent in order to generate evidence that a Democratic victory is tantamount to ‘mob rule,’” as was described in a recent report. (Atlantic staff writer David Frum is a participant in the project.)

In interviews at the rally here yesterday afternoon, Trump supporters told me a Biden victory is so implausible that it could come about only through corrupt means. Latrobe sits in a county where Trump defeated Hillary Clinton four years ago by a 2–1 margin, and no one I spoke with thought Trump was in any real danger of losing this race either.

Walker spoke of a potential “revolution” were that to happen. “He ain’t got a prayer,” Walker said of Biden. “He can only win with fraud.

“That’s the only prayer, and that will cause the third and final revolution in this country,” he added, citing the Revolutionary War and the Civil War.

Before I entered the airplane hangar where the rally was held, I spoke with John and Michele Urban, a couple from Latrobe, as they waited in line to get inside. “Either way, there’s going to be turmoil,” Michele Urban said. “A revolution. I’d never thought I’d live to see it. I’m 66 years old.” Her husband, 68, told me: “Democrats have sealed their own fate. They’ve proven they’re not true Americans. They’re not for this country, and they’re not for our freedom. We’re just not going to take it any more. Trump is a godsend.”

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