Late in the 2016 presidential campaign, an anonymous author, eventually revealed as Michael Anton, a conservative scholar who later joined the Trump White House, described the race between Donald Trump and Hillary Clinton as the “Flight 93 Election.” In his widely read essay, Anton insisted that a Democratic victory would change America so irrevocably that conservatives needed to think of themselves as the passengers on United Airlines Flight 93 on September 11—the ones who chose to bring down the plane to save the U.S. Capitol from al-Qaeda hijackers. Letting the Democrat win, in other words, would doom the country.

Trump supporters’ rampage on Wednesday represented a bracingly physical expression of that belief—and a bitterly ironic inversion of it. To save the country, in their eyes, the pro-Trump rioters assaulted the same building that the actual Flight 93 passengers died to protect.

The riot showed how the ominous tenor of contemporary Republican messaging could be fueling white conservatives’ extremism. For at least the past decade, GOP candidates and conservative-media personalities have routinely deployed rhetoric similar to the Flight 93 argument. Only about 40 hours before the insurrection, at a campaign rally hosting an enthusiastic, virtually all-white audience in rural Georgia, President Trump insisted that if Democrats won the state’s two Senate runoff elections this week, “America as you know it will be over, and it will never—I believe—be able to come back again.”