It's been a heckuva day for the trolls.

In just one day, the so-called "alt right"—a political faction that spreads white supremacist ideology primarily online—has come to dominate the national news cycle. Today, they've had a hashtag, #AltRightMeans, trending on Twitter; they've gotten high praise from Donald Trump, who swore up and down this community isn't racist; and then came the cherry on top: an impassioned speech by Hillary Clinton in which she called out their members, who have banded together behind Trump, by name.

What more could a dark army of trolls want? It didn't take long until they started celebrating on the same online portals they've used as recruiting tools since the term "alt right" first popped up around 2008.

This once-fringe movement is now standing center stage. In her speech today, Clinton called Trump's decision to hire alt-right champion Steve Bannon, formerly of Breitbart News, a "landmark achievement for this group."

"There's always been a paranoid fringe in our politics, a lot of it arising from racial resentment, but it’s never had the nomination of a major party stoking it, encouraging it and giving it a national megaphone until now," Clinton said. She's right about that, but she missed an important point. Trump isn't the only one giving the alt-right a microphone. So is social media.

To be clear, there is only one answer to the hashtag #AltRightMeans. It means white supremacy.

To be clear, there is only one answer to the hashtag #AltRightMeans. It means white supremacy, researchers say, plain and simple.

"Race is at the foundation of everything to the alt-righters," says Mark Potok, a senior fellow at the Southern Poverty Law Center, which tracks the alt-right movement as a hate group. "They have this idea that white people and white civilization is under assault by the forces of political correctness, by social justice and so on."

The term "alt-right" is merely a rebranding of an ideology with deep, dark historic roots, says Jessie Daniels, a professor of sociology at Hunter College and author of the book Cyber Racism. In fact, you could say it's a "dog whistle" for white supremacy. "People who are in the United States, mostly white people, are uncomfortable saying white supremacy," Daniels says. "They're more comfortable saying alt-right"

And social media has been an important vehicle for that rebranding, she says, because it's a place where, for better or worse, all ideas can have equal weight, regardless of where they originate. "It creates an equivalence of ideas, the undermining of expertise," Daniels says. "That’s part of what has given them more power. No one's an expert or everyone's an expert. White supremacists saw that and got that early on and use that to their advantage."

Where white supremacists once gathered around a burning cross, now they gather on 4chan, in white power Reddit forums, and hashtags like #WhiteGenocide, and in the comments section for media outlets like Breitbart. Where the Ku Klux Klan had its own nomenclature, alt-righters have developed their own social media slang and portmanteaus, like "cuckservative," a combination of the words "cuckold" and "conservative." It's a racially tinged and sexually charged term, Potok says, that refers to white men allowing black men to have sex with their wives. They even have their own unifying symbols, like the "echo," three enclosed parentheses used to single out Jewish names, and Pepe the Frog, a meme now commonly used by the alt-right.

What's more, Daniels says, the Internet lets white supremacists around the world unite, no matter where they live or what specific grievance is stoking their bigotry. "It makes an explicitly racist white identity possible across national boundaries," she says. In that way, these white nationalists have created their own nation with its own rules of entry, its own values, and its own language. It's just that this nation lives online.

There's little doubt that Trump is now its de facto leader, but this week, Trump has been trying his best to distance himself from this darkness. In a town hall with conservative talk show host Sean Hannity, he walked back his promise to deport 11 million undocumented immigrants from the US. And during his speech today, he cast Clinton's efforts to exploit his support among known white supremacists as "tired."

"It’s the oldest play in the Democratic playbook," Trump said. "It’s the last refuge of the discredited politician."

But Clinton didn't appear tired in what was, perhaps, this election season's most scathing rebuke of Trump's candidacy. Clinton condemned Trump for "taking hate groups mainstream and helping a radical fringe take over the Republican party." She reminded voters of Trump's well-documented roots in the birther movement, which tried unsuccessfully to prove President Barack Obama wasn't born in the United States. She mentioned the time Trump retweeted the Twitter account of a neo-Nazi.

She highlighted Trump's failure to disavow Klansman David Duke and compared Trump's plans to institute an ideological test to the type of thing the Islamic State does to control its own population.

"What a cruel irony that someone running for president would equate us with them," she said.

She noted the Justice Department's racial bias suit against Trump, which accused his real estate management firm of discriminating against black renters and marking their applications with a "C" for "colored."

But the impact Clinton's speech has had—eliciting so many gleeful responses from the very people she was denouncing—also reflects just how difficult it is to stop the alt-right movement from metastasizing. Like the parent of an unruly child throwing a tantrum in the super market, she has a choice: to condemn that behavior loudly and publicly at the risk of escalating the drama or to ignore it altogether and risk being irresponsible for allowing it to continue ceaselessly.

And now that the trolls have come out from under the bridge, it's a choice we all must face.