AUDIE CORNISH, HOST:
Houses of worship are places to pray, to connect to community. And increasingly, they are targets of extremist violence. The latest target - the Chabad of Poway synagogue near San Diego. A gunman stormed in on Saturday during services and killed one person. Three other people were injured.
J M BERGER: I really was just feeling very weary. You know, it was not a big surprise to see another incident.
AILSA CHANG, HOST:
That's J.M. Berger, author of the book "Extremism." The San Diego County Sheriff's Department has said it believes the 19-year-old suspect acted alone. But J.M. Berger says his attack is connected to other white supremacist attacks all over the world. This connection is laid out in what's believed to be the suspect's anti-Semitic manifesto, which was posted online just before the attack.
BERGER: What jumped out at me immediately was that this was very closely connected to the Christchurch shootings of just a couple of weeks ago. The shooter had modeled his attack after Brenton Tarrant, the killer who carried out that attack.
CHANG: What are connections that you find, as someone who has studied manifesto after manifesto left behind after horrendous incidents like this?
BERGER: Typically, these documents are intended to assign meaning to an act of violence that might otherwise be perceived as meaningless. So it says, this is not senseless violence. This is not - I'm not a lunatic. I'm trying to accomplish something specific. And it allows other people to latch on to that and, ultimately, it leads to more violence.
So in the case of Anders Breivik, who killed almost 80 people in Norway a couple of years ago, and in the case of Dylann Roof, who killed nine people in Charleston a couple of years ago, both of them left manifestos outlining their extremist beliefs. And in a lot of the cases that we've seen over the last year, those two figures in particular are often cited as examples.
CHANG: What's sort of the broader ideology that is at play here?
BERGER: It's white supremacy. I mean, it is definitely the promotion of a white European descent kind of in-group against anybody who doesn't fit that definition. But the frame that we see for this right now - and it's not necessarily a new frame, but it's particularly notable right now - is that, you know, a lot of this hostility, a lot of this racism and bigotry is really being phrased in an immigration context.
CHANG: And can you literally trace how the concepts expressed in these manifestos spread geographically as these manifestos are sent and forwarded and posted?
BERGER: There's very little limit on how they spread geographically. Now, if you go back to the 1980s and 1990s, extremist ideologues had to make a videotape. And then that videotape would be passed around. Somebody would have to carry it somewhere or mail it somewhere. This process was expensive, and it was slow. And with the rise of the Internet, an extremist ideologue or a mass shooter can create a document, distribute it instantly to thousands of people who then spread it to thousands more. And there is very little friction to stop that from happening.
CHANG: You know, we often hear the phrase lone wolves when talking about the people behind these murders. But is the phrase lone wolf a misnomer if many of these seemingly lone individuals are just motivated by each other?
BERGER: Yeah. A lot of us who work in this field are very down on the phrase lone wolf. In almost every case, what we see is that people are acting out of a social context. They have a social network that's supportive. They have an audience they know and that they're playing to. And the phrase lone wolf can kind of imply that there's not this big social infrastructure behind someone.
CHANG: J.M. Berger is the author of the book "Extremism." Thank you very much for speaking with us today.
BERGER: Thank you for having me.
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