“So the reply space is a media channel unto itself,” said Justin Hendrix, the executive director of NYC Media Lab, a public-private partnership that connects universities and technology companies. “You see various people, including professional journalists, taking advantage of it. This morning, [the New York Times columnist] Nicholas Kristof was one of the first respondents to Donald Trump’s tweets about Russia.”

.@realDonaldTrump That was a fine example of Russian manipulation, selectively stealing and sharing emails to put its buddy in office. — Nicholas Kristof (@NickKristof) December 16, 2016

“You see political activists, you see comedians,” Hendrix added. “There is no doubt it drives engagement.” That’s because Trump’s tweets are, Hendrix says, “probably the most consumed tweets on the planet.” But it’s not just that. Trump is unpredictable, informal, and often antagonistic in his communications style. He sets the tone for confrontation. Some see it as a badge of honor to be blocked by Trump. (Or, depending whom you ask, evidence of fascism.) That said, people obviously gravitate toward confrontation online anyway—and especially on Twitter. (President Barack Obama’s tweets often read like something out of a boring press release, and even those generate a swell of responses, often in the form of racist attacks against him.) And while plenty of the people who reply to Trump seem interested only in name calling, there are others who view the space as a way to pierce the so-called filter bubble—to challenge Trump publicly when he spreads misinformation.

I reached out to Hendrix in the first place because I’d noticed he was the first to reply to several recent Trump tweets—including the one from this morning. Trump tweeted: “Are we talking about the same cyberattack where it was revealed that head of the DNC illegally gave Hillary the questions to the debate?” Hendrix replied: “Donald colluding with the Russians would be a much bigger crime. In fact it would be a crime; what the DNC did was not.”

Turns out, however, that Hendrix wasn’t actually the first first to reply to Trump this morning. Because I follow him on Twitter, his reply was the first I saw. Twitter made it look like he was first to me because Twitter’s algorithms have, for some time now, personalized some views of the site based on who a person follows. (You can tell the difference between a neutral view of Twitter responses to Trump and your personalized view of them if you look at Trump’s tweets in an incognito browser.)

Notching the first-reply spot for any Trump tweet—let alone several of them—takes a combination of super-speed and luck. You’re up against countless people and bots—and the bots are programmed to reply automatically to Trump as a way of leveraging his reach.

This bot activity includes an entire cottage industry of internet-designed T-shirts and mugs, with bots advertising slogans like “enjoying my hot cup of liberal tears,” all within replies to Trump tweets.

At least some of Trump’s followers are bots, too. Though, as my colleague Andrew McGill discovered, it’s difficult to determine how many. Whatever the case, the humans who pay attention to Trump’s tweets are likely to wander into the replies at some point, either deliberately or because responses to Trump tend to be widely shared themselves.

@realDonaldTrump Donald colluding with the Russians would be a much bigger crime. In fact it would be a crime; what the DNC did was not. — Justin Hendrix (@justinhendrix) December 16, 2016

In a broad sense, the public sphere that has emerged in Trump’s Twitter replies isn’t a new phenomenon. Much ink has been spilled dissecting the snake-emoji attack on Taylor Swift’s Instagram account. “A few years ago, everybody talked about Justin Bieber’s Twitter account,” Hendrix said. “No one talks about Bieber anymore. They talk about Donald.”