One of the Internet’s top sites for racists, a subdomain of the popular Reddit empire, is in an uproar right now. A white man apparently acting out of racial hatred killed nine black churchgoers in South Carolina on Wednesday night, and this subreddit’s racists are asking themselves questions in the wake of the massacre. How will the murders affect us? they want to know. Is this good for us racists?

“Today, A Lone Gunman will represent all of White America,” one user on the r/coontown subreddit moaned Thursday, “while thousands of black-on-white crimes constitute random acts of (non-racially motivated) violence.” That’s typical of the more muted reactions from the subreddit’s anti-black activists. Other posters were panicked, preparing for the coming race war. A few condemned the violence, with strenuous caveats to ensure their peers that doing so didn’t make them less upstanding racists. Some were giddy after Wednesday’s shooting.

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Outside Reddit’s fever swamps, some of the same questions are being asked about the website, which rightly prides itself on being a platform for free speech. Anyone can get on Reddit. Registration is anonymous, free, and takes only about a minute. Users can then create sites within the site, called subreddits, based around specific communities or interests. There are subreddits for funny videos, science, and retro pictures. President Obama dropped in to do a Reddit AMA (“Ask Me Anything”), a stop celebrities routinely make on their promotional tours.

That’s the front of the house. But Reddit is vast, and with the majority of users pursuing more innocuous interests, it’s easy to ignore what’s going on in the cellar.

Reddit calls itself the front page of the Internet. With more than 172 million unique visitors last month, that’s a fair claim. It may not be where every popular meme is created, but it’s likely where you first see them, and insofar as there’s a shared cultural experience on the Internet, Reddit provides it.

It’s also one of the Internet’s largest gathering places for racists. And those racists have been fighting to protect their safe space, defending their right to call people the n-word and celebrate violence by wrapping themselves in the banner of free speech and warning about the specter of social justice warriors.

Last week, Reddit banned a number of sites on the grounds that they were harassing people—but left the vast majority of its sites advocating racial and religious hatred untouched. R/fatpeoplehate, which became one of Reddit’s most popular forums by encouraging the shaming and harassment of people it found overweight, was shut down. Other sites, including r/watchniggersdie, r/gasthekikes, and r/rapingwomen, were untouched and are still operating.

The decision, laid out in a statement from Reddit’s administrators, was intended to prohibit certain actions without impeding the free exchange of ideas for which it’s famous. “We will ban subreddits that allow their communities to use the subreddit as a platform to harass individuals when moderators don’t take action,” the admins wrote. “We’re banning behavior, not ideas.”

Banning ideas would undermine what Reddit is all about. The site grew into a web titan in no small part because it clung tightly to a founding principle of the commercial Internet: that people were free to say whatever the hell they wanted. While the rest of the big digital players moved toward more and more heavily manicured environments—try to post a picture of a topless woman on Instagram—Reddit stayed pure, wild.

The new bans led to an outcry from Reddit users while sending new subscribers over to r/coontown, which saw its membership spike in the days after the other sites were shut down. Outraged Redditors attacked the company’s leaders, whom they accused of kowtowing to censorious activists and undermining the site’s principles. Fat shaming, some argued, was a jab in the eye of political correctness, and a form of offensive but legitimate political speech. The stuff about harassing people was no different from what other subreddits were engaged in, a common complaint went; the punishment was really for rejecting the liberal orthodoxy.

Taking up a similar First Amendment cry, Reddit’s thriving racist community defends itself in much the same way. It, too, rails against oppressive social justice warriors. Fat shaming and racial hatred wouldn’t seem to have much in common besides a shared poverty of spirit that makes believers act like vicious creeps, but in both cases, and as with any strongly held ideas, speech can shade into action. There’s a critical difference between harassing individuals anonymously about their weight and endorsing a legacy of racial violence that has blighted American history. But the same speech protections, often phrased in the same ways, are being claimed by both groups.

Any abridgement of speech can have unforeseen consequences. But there are circumstances, especially around speech encouraging violence, that sometimes require prohibitions. We’ve come to understand that as a commonsense principle when it comes to Islamist terrorism, even as it’s been imperfectly applied and sometimes overextended. (Think about the question asked after every Islamist terrorist attack: “How was he radicalized?”)

The rhetoric that surrounds American political violence, on the other hand, doesn’t always get as much scrutiny. Twenty-first century American racial hatred traffics in the same ideas the old KKK espoused, but in places like Reddit it’s learned some new tricks. One gambit is to speak in terms of “racial realism,” dehumanizing black people as a rational corrective to liberals’ belief in equality. Another is to couch racism as satire, gaining some wiggle room by speaking in terms of provocations rather than political programs. Of course, we can all see past the wink and the nod.

In an article posted to Gawker in March, the Southern Poverty Law Center’s Keegan Hankes wrote, “Reddit increasingly is providing a home for anti-black racists—and some of the most virulent and violent propaganda around.”

Part of what is attracting racists to Reddit, Hankes told me, is that its posting rules are less restrictive than those enforced on more established websites with exclusively white supremacist agendas.

“One of the most striking things is you can put up videos showing black people being killed,” Hankes said. There’s even a subreddit devoted to that called r/watchniggersdie. It’s the kind of material that’s “found a home on a subreddit under the banner of freedom of speech,” Hankes said. “This can’t exist on the worst white supremacist forums, but it can under Reddit.”

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The subreddit r/coontown, named for an anti-black racial epithet, currently has 15,540 subscribers and ranks 2,279th among the site’s 9,528 subreddits. The subreddit was in the news last week because it survived Reddit’s ban. That’s put Coontown’s moderators on edge and made them extra attentive to Reddit’s rules. Mindful of the site’s distinction between actions and ideas, those moderators were busy Thursday deleting comments that could be construed as advocating violence or harassment. The subreddit’s members, meanwhile, were wary of incoming media attention from “Jew owned media.” (Hi, fellas.)

“Stuff like this is what gives Jews and SJWs ammo,” one user wrote. “Shit,” another member lamented. “The Al Sharptons and anti-gun Jews are going to have a field day with this. This is better than anything they could have hoped for to push their narrative of being oppressed by ‘de ebil yt man.’”

A r/coontown user calling himself Leaningtowerofbro implored his fellow racists to condemn the Charleston massacre. “Do NOT be this fucking piece of shit,” the member wrote. “I’m one of us and he DOES not represent me. Regardless of my views, this is not ok. This is emulating the behavior we despise!”

Leaningtowerofbro is only one member of a chorus on r/coontown bemoaning that racist murders will unfairly taint racists. But even that kind of thinking was too soft for some of the subreddit’s members and forced this clarification: “I am not being an apologist by any means. I don’t feel guilty for what he did.” That was not enough for a member called mciracer, who wrote back, “Yes you are, n---ers are dead; celebrate.”

Celebrating “dead n---ers” is only an idea, only words, but that idea is a tribute to violence.

R/coontown’s users must have noticed, as some of them acknowledged, that the words ascribed to South Carolina’s gunman were the same words they used, the same ideas. “I have to do it,” Roof reportedly told one of his victims. “You’re raping our women and taking over the country. You have to go.”

From a murderer’s mouth to a racist Redditor’s ears.

“I don’t think he was insane or mentally ill,” one Redditor wrote in response to the quote on a post that drew 20 other supportive comments. The facts are still coming in about Roof, but if he saw himself avenging white women’s rape at the hands of black men, that would put him in an American tradition of racist political violence that goes back centuries and is well preserved on r/coontown. Warnings about white women’s despoilment by black men is one of the oldest tropes of white supremacist bigotry, a subject of countless posts on r/coontown, and an idea that is explicitly a call to action. Someone has to defend white women from predatory black men and, as the KKK’s history shows, the defense is a suitable pretext for violence and racial terrorism.

For more than a decade online, public forums have been figuring out how to deal with jihadists taking advantage of the free space they offer. Twitter, for example, has been shutting down accounts (PDF) associated with ISIS—not as actively as it could, critics say, but enough to have dented ISIS’s online operations.

Currently there are no pro-ISIS subreddits. Perhaps that’s a bridge too far even for Reddit, though a company spokeswoman wasn’t able to comment when asked whether a subreddit would be allowed to advocate for the group as long as it didn’t engage in prohibited behavior like harassing individuals.

Expanding on Reddit’s rules, spokeswoman Heather Wilson provided this statement to The Daily Beast:

“We created these anti-harassment policies because our ultimate goal is to ​encourage authentic conversations and idea​-​sharing on an open platform​ with many voices participating​. The Internet is an evolving medium and presents a number of challenges​ at scale, ​and we’re learning and hopefully ​improving our place in it. While we do not always agree with the content and views expressed on the site, we do protect the right of people to express their views and encourage actual conversations according to the rules of Reddit.”

Encouraging authentic conversations and idea sharing is a laudable goal, essential to a free society and to Reddit’s image and business model. It’s also easier said than done. Banning some conversations invariably opens the door to more, and more capricious, bans. Refusing to regulate speech at all can be a recipe for mob rule and, as in jihadi forums, a free space for people to promote violence.

Reddit is trying to thread the needle. So are the site’s most hateful users. There’s a canniness to even some of the most virulently racist postings. Users are careful to balance on the edge of Reddit’s rules, where the line between smirking at violence for kicks and encouraging it because you want to see people hurt doesn’t necessarily matter as long as you haven’t picked out a target.