"Who is coming into this country, and who is coming into your school, that's been trained like this?" asked an instructor. "They've been trained for this all their lives." A PowerPoint slide projected in front of the classroom urged those caught in a firefight to listen carefully between gunshots for invocations of Allahu Akbar. "Pay attention to that," he said. "That's a clue."

It is the first day of FASTER Saves Lives, a three-day seminar at which teachers and staff members learn to carry concealed handguns on campus. (I wrote about the experience earlier this year for GQ.) This instruction came during the introductory lecture, which was mostly an overview of the history of American gun violence but also featured a brief, startling aside: a slickly-produced and extremely graphic video of children stalking through an abandoned house, chasing down unarmed, screaming, handcuffed prisoners and executing them in the hallways. There were brains and bullet holes. One victim jumped off the roof to avoid being shot; the miniature soldiers looked down wordlessly at his crumpled body.

The video in question, it turns out, was an ISIS propaganda film released in 2017. And the purpose of showing it to two dozen school employees, it turns out, was to warn them about the possible types of people they'd spend the next three days preparing to defeat in armed combat. Visually, it was not much different from the footage live-streamed by an Islamophobic terrorist on Friday, as he raced through two Christchurch mosques and killed 49 people in their houses of worship.

Judging from the shocked facial expressions around the room, I was not the only participant who found this segment of the curriculum to be unsettling. But for some people, it seemed to have its intended effect: During the next break, there were a few spooked whispers about "sleeper cells" and the latent dangers they could pose to unsuspecting communities. "That video could change a lot of minds," one man said somberly. He was referring, of course, to public opinion about the controversial purpose for which we were all gathered in the first place: teaching teachers to exercise their Second Amendment rights to the fullest.

I am thinking about this moment a lot today, particularly as I read excerpts from the Christchurch shooter's trolling manifesto. It is littered with sarcastic, innuendo-laden Internet-speak—in-jokes that racists deploy to protest accusations of racism while winking at allies who find such accusations hilarious. (He credits Fortnite for teaching him to “floss of the corpses of my enemies,” for example, and Spyro the Dragon—a kids' video game—for introducing him to ethnonationalism.) But even if there are elements of a trolling performance, his invocations of the Second Amendment reveal a keen understanding that guns, especially in the United States, can provide a dependably easy entry point for those who traffic in hate to reach people who may be susceptible to that message.

"I chose firearms for the affect [sic] it would have on social discourse, the extra media coverage they would provide, and the affect [sic] it could have on the politics of the United States and thereby the political situation of the world," he wrote. Under sufficient "pressure," he said, the country's gun-safety faction would seek to abolish the Second Amendment, and the gun-rights contingent would react to this threat in kind, prompting a "dramatic polarization of the people" and a "fracturing...along cultural and racial lines." Whether the shooter intended this as sincere or not, what remains is that he is participating in a dialogue of white supremacist violence—like Norwegian far-right terrorist Anders Breivik and Oklahoma City bomber Timothy McVeigh—which is rooted in both hate and a particular strain of gun rights ideology.