In the weeks since Dylann Roof murdered nine people at the Emanuel African Methodist Episcopal Church in Charleston, South Carolina, the country has catapulted into a conversation about hate groups, white nationalism, and the threat of domestic terrorism.

Senate Democrats are calling for Congress to shift its focus from solely jihadist-fueled terrorism and hold hearings on the threats from domestic groups in upcoming weeks. And the Department of Justice has already opened up a domestic-terrorism investigation into the Charleston church shooting.

The Southern Poverty Law Center says that while symbols like the Confederate flag may be under fire and groups like the Ku Klux Klan may be in decline, other sects of the white-pride movement are still very much intact and growing. That's thanks in large part to the power of the Internet.

"What we are seeing is that large groups of people are leaving groups for lots of reasons and going onto the Internet," says Mark Potok, an expert on extremism at the Southern Poverty Law Center, which tracks hate groups. "It really happened rarely in the 1990s that a person got recruited online, but that pattern is picking up."

In his alleged manifesto, Roof claimed it was the Council of Conservative Citizens' website that first alerted him to "black on white" crime.

"The first website I came to was the Council of Conservative Citizens. There were pages upon pages of these brutal black on White murders. I was in disbelief. At this moment I realized that something was very wrong," reads the manifesto, which the FBI said likely belonged to Roof.

Outbreaks of violence from groups like the KKK are rare, but the dawn of the Internet has allowed for more self-radicalization, Potok warns. And lone-wolf crimes are among the hardest to track.

"A lot of crimes are not committed by card-carrying members of these groups at all," says Mark Pitcavage, the director of the Anti-Defamation League's Center on Extremism.

According to a report by the SPLC, of the 60 successfully executed or foiled domestic-terrorism plots planned between April 2009 and February 2015, 74 percent of them were organized by lone wolves and 90 percent were carried out by just one or two people.

As is the case for any advocacy group, social media, web forums, commenting sections, and websites have emerged as key education and recruiting tools for the white-nationalist movement. Experts say that as white nationalists' views are increasingly marginalized in American culture, sympathizers retreat to parts of the Internet, where they may be free from criticism and where factions within the movement connect with sympathizers across the globe.

"The social cost of being associated with these groups has grown very rapidly," Potok says. "The net has become the first language for a whole cohort of people, especially young people like Dylann Roof."

The SPLC still says the sheer number of hate groups has grown over the last several years, but more growth has still occurred online. As of 2014, SPLC identified 764 hate groups within the United States. Roughly 115 listed on the website are active white-nationalist groups, 72 are Klan chapters, and 119 are racist skinhead organizations.

Yet, for many individuals, the anonymity of online comment sections and forums like Reddit and Stormfront provides a safer space to project controversial thoughts on race. SPLC says that Stormfront—the forum founded by former KKK member Don Black, which claims to be "the voice of the new, embattled White minority!"—has 300,000 registered users, far more than the number of people who are thought to belong to any Klan or formal white-nationalist group. On forums, writers post about the need to "PROHIBIT black music from our ears as much as humanly possible while replacing that garbage with pro white music" and express concerns about the "insane non-white immigration that is changing the composition of the United States, from what it was."

Jared Taylor, a self-proclaimed "race realist" who acted as a spokesman for the Council of Conservative Citizens following the Charleston shooting, says his own group and magazine does not use the Internet any differently than other interest groups, but he also does not believe claims that Roof was influenced to commit violence by the Internet.

"What Dylann Roof did with that information is something that cannot be blamed on the Council of Conservative Citizens," Taylor says. "I don't know of anyone, absolutely anyone certainly in the broad white-advocacy movement who advocates violence or illegality of any kind. Our website presents information and it draws conclusions, it never ever advocates illegality. It is not our fault if someone were to go crazy and for some reason act violently off of this information."

Taylor is the founder of the New Century Foundation and he helps run American Renaissance, a website that shares podcasts, videos, and articles which he says promote white culture. The website claims: "When there is significant demographic change, the entire texture of life changes. One of the most obvious consequences of an increase in the black population is an increase in crime." The SPLC describes Taylor's work at the New Century Foundation as "'research' arguing for white superiority." His group has published studies on race and crime, which claim that "[t]he single best indicator of violent crime levels in an area is the percentage of the population that is black and Hispanic."

Taylor says that in recent years, it has become harder for his group to arrange conferences at hotels, which has made the Internet a more important tool for getting the word out. Beginning in 2010, event managers began backing out of hosting Taylor's groups because of the backlash they received.

Richard Spencer, who is well-known for his academic packaging of white-nationalist themes, says that his movement has taken advantage of the Internet just like anyone else.

"A lot of this is hiding in plain sight," Spencer says.

And, while the Internet has provided cover for some who are too nervous to meet in person, it has also helped his group organize in the real world.

"Even holding a meeting before the age of the Internet was a lot more difficult. The meeting in the physical world and meeting in the virtual world has reinforced each other," Spencer says. "I don't think as many people would come to the conferences I organize or even find out about them without the Internet."

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