To outsiders, #GamerGate looked like a cesspool of angry, entitled young men nobody else wanted to talk to. But some right-wing figures spied an opportunity. Mike Cernovich, author of a hypermasculine self-help blog called “Danger and Play,” joined the cause. (“I use trolling tactics to build my brand,” he later told The New Yorker.) So did Milo Yiannopoulos, then writing for the website Breitbart News, which helped midwife the controversy from a fringe freakout to a right-wing political perspective. (“I hurt people for a reason,” he said recently. “I like to think of myself as a virtuous troll.”) Donald Trump saw political promise in this world, too: As his White House bid seemed on the brink of collapse last summer, he found a new campaign manager in the Breitbart executive chairman Stephen K. Bannon, a sincere nationalist with trolling tendencies of his own.

Now, Bannon sits on the National Security Council, and many Trump supporters are fusing the trolling ethos with old culture-war tropes, amusing themselves by calling liberals delicate “snowflakes” and delighting at being “in” on Trump’s “joke.” As the right-wing columnist John Feehery put it after Trump’s Feb. 16 news conference: “Performance art can be so hard for normal people to understand.” People like Cernovich — who jumped easily from #GamerGate to the Trump train — have taken to calling their political posture “antifragile,” Nassim Nicholas Taleb’s word for systems that thrive on volatility and stress. Trump, Taleb has said, is “heavily vaccinated because of his checkered history” — nothing new can shame him. Nothing matters.

The troll figure feels as new as the smartphones in our hands, but his trail of destruction stretches deep into history. Toward the end of World War II, Jean-Paul Sartre looked at the anti-Semites of Europe and saw something that still sounds familiar. “Never believe that anti-Semites are completely unaware of the absurdity of their replies,” he wrote in the 1944 essay “Anti-Semite and Jew.” They “are amusing themselves, for it is their adversary who is obliged to use words responsibly, since he believes in words.” Anti-Semites “delight in acting in bad faith, since they seek not to persuade by sound argument but to intimidate and disconcert.”

Recently we’ve witnessed a resurgence of this winking Nazi type. PewDiePie, a wildly popular YouTube video-game star, filmed a “prank” in which he hired two men to hold up a sign that said “Death to All Jews.” Pepe the Frog, an online cartoon that morphed into a 4chan meme, has been co-opted by plugged-in fascists who redraw him with swastikas for eyes. And after the white nationalist Richard Spencer, a man who has voiced support for “peaceful ethnic cleansing,” yelled “Hail Trump” at a Washington conference and received Nazi salutes from crowd members, he claimed it was all “ironic.” These days even David Duke, a sincere and straightforward white supremacist, is sharing racist memes and getting called a “troll.” But when Spencer showed up in Washington for the inauguration, explaining his Pepe lapel pin to the press, a masked protester ran up and collapsed all that ironic distance by punching him in the face.

Trolls work through abstraction, leveraging the internet and irony to carve out a space between actions and consequences. Becoming president has blown Trump’s cover: There’s nothing more consequential than this. Trolls are typically outsiders, and sad ones: They don’t fit into the dominant group, so they terrorize it from the sidelines. Part of what makes Trump’s administration so alarming is that the troll sensibility now dominates. And when that happens, it’s reminiscent of what Sartre described: No reason, no principle, just the pure exercise of power.