Even if, as Newsweek's Matthew Lysiak pointed out today, Dylann Storm Roof was "taking a drug that has been linked with sudden outbursts of violence," suggesting that perhaps the mass murderer was maybe suffering from mental illness (my hunch is that he was just a pill popper), the fact of his possible mental illness doesn't mean that in America his ideas are considered "crazy," especially not to certain organizations.
One such organization is Stormfront.org, a white supremacist website that features several forums and a fucking chat room and has been linked to nearly 100 hate-crime murders, the Guardian reported last year. In the piece, Heidi Beirich, the author of the study that researched this information, said: “The fact of the matter is that more people have been killed domestically by radical right extremists than Islamic extremists since 9/11, and where you find a lot of these people is on these sites."
You don't have to dig through obscure sites to find possible sources for Roof's notion that black people are "taking over" and "raping our women." When Obama was running against McCain back in 2008, little old grannies were confessing their fear that an Obama victory would lead to a "black takeover." You've got Bill O'Reily telling 4 million people that, "overwhelmingly, violent crime in this country is generated by black men." These are the claims floating around, the claims that allow Roof to construct the argument that he had to kill those innocent people.
Even more broadly, these ideas are fossilized in racist jokes, which Roof used all the time, one of his few friends claimed: “He made a lot of racist jokes, but you don’t really take them seriously like that. You don’t really think of it like that.” But we should be taking them seriously like that. When we repeat racist jokes we perpetuate the stereotypes they rely on. In part, we're saying that the world really does work like this racist joke says it works. That world is fucked up.
Many writers have cited the state flag of South Carolina itself as a symbol that encourages the kind of "Southern pride" that can lead to mass murder. You don't have to live in South Carolina to see that flag. Growing up in Missouri, I saw the "Stars and Bars" on license plates, belt buckles, the walls of my friends' houses. You can find the fucking thing on a teddy bear.
Though some still deny it, there are books and books and books and books that detail the pervasive and institutional nature of white supremacy, the way it creeps into our everyday actions, the way it provides a logic and a vocabulary for murder. Like anyone else, Roof is a filter through which American culture passes. So what if his filter's possibly bad? It only serves to show how common, how mainstream, how sick these ideas are.