Nearly 20 years after 9/11, determining the profile of someone who is going to join a terrorist group remains a deeply challenging effort. For too long we have looked at simple explanations—like poverty or lack of education—for why people join violent movements. Erdberg discusses a new project to investigate the psychology and neuroscience that motivates people to resort to extremism.

On Peace is a weekly podcast sponsored by USIP and Sirius XM POTUS Ch. 124. Each week, USIP experts tackle the latest foreign policy issues from around the world.


Tim Farley: Let's turn to the serious business of terrorism and why people go to the dark side. That's an oversimplification, but we are looking at, or our next guest is part of an effort to look at what exactly it is that motivates people to join groups like ISIS.

Tim Farley: Leanne Erdberg is the Director of Countering Violent Extremism, or CVE, at the U.S. Institute of Peace. The Twitter handle is @USIP, and she joins us now. Leanne, welcome. Thank you for being on the program today.

Leanne Erdberg: Thank you so much for having me this morning.

Tim Farley: There are many questions. People, for example, remember the case of Hoda Muthana, who had left the U.S. to join ISIS. She was declared not a U.S. citizen, but one wonders, why do you leave a seemingly decent place to be to go to a place that is so dark? Tell us exactly how you're trying to approach this, the way to discern motivation and what makes people do what they do.

Leanne Erdberg: I think it's a great question. We're almost 20 years after 9/11, and people have joined terrorist groups from all walks of life, that with all sorts of diverse backgrounds, and trying to figure what is the single profile of somebody who is going to join a terrorist organization as a fighter or as a supporter has really defied our abilities for prediction. What we are trying to do is understand at the psychological level, as well as at the structural level, how these emotions manifest in the brain. We're pursuing pretty interesting partnership with some neuroscientists, who we hope can tell us what it looks like in the brain when you're striving for a sense of purpose or a sense of meaning as a part of a group, what it means to feel excluded or hopeless or marginalized and what sharing a bond and being on a shared mission looks like in your brain.

Tim Farley: That sounds vaguely like people who join cults.

Leanne Erdberg: I think there's a lot that we can learn from people who join cults. The idea that violence is an antisocial norm is often taking as just the bottom line. We all hate violence, but it's remarkably normal in a lot of places around the world. In a group, you can feel like violence is normal, even if our social norm is that it's abnormal. Cults were able to do that pretty successfully for a period of decades, and I think terrorist groups are doing it pretty successfully today.

Tim Farley: We had spoken not too long ago with Farah Pandith. She's written a book called How We Win, and she talked a lot about CVE. This is, again, trying to get to the root cause. You said, in the beginning of our conversation, that it's been 20 years since 9/11. Was there this kind of recruitment, this kind of movement to this sort of a group before that? Was it different from the way it manifests itself now?

Leanne Erdberg: I think the historical prevalence was much less pre-9/11. The numbers of the last 20 years show that we have more terrorist groups in more places committing a grand diversity of attacks, but I think that the history of why people join politically violent movements have a lot to give us, and I think that we have ways in which we can learn from many historical struggles, particularly on how those historical struggles end.

Tim Farley: I wonder how much of this is about the political philosophy and the political bent, if you will, of these organizations and how much of it is just that personal aspect of the individual who's seeking something regardless of what that philosophy might be.

Leanne Erdberg: I think it's both. I think, for a long time, we were looking for really oversimplified answers to why somebody was joining a group. It was because of poverty or they didn't have the right type of education or religion was leading them down the wrong path.

Leanne Erdberg: I recently saw a study that there's over fifteen factors of why children in one specific school district had inattention in the classroom. If we can get to fifteen factors of why children don't pay attention to their teachers, I think we can at least think about why people join terrorist groups, as they're equally complex and equally context-specific.

Tim Farley: Leanne Erdberg is Director of Countering Violent Extremism at the United States Institute of Peace, joining us here on POTUS.

Tim Farley: There is one step of withdrawing from the situation that an individual finds himself or herself in, but there's another step, which is moving to violence. I guess there's a big question to is, how would somebody reject not just maybe the social construct that they believe was important as a part of growing up, but then would move to a very aggressive or even violence persona to be a part of these groups.

Leanne Erdberg: I think that this is a really important point that some of the neuroscientists that we've been partnering with have given me a lot more information, and it's not always linear. People don't always turn to the violence after they're radicalized. There are plenty of groups around the world where they were part of militias and insurgencies before they aligned with terrorist groups, but perhaps more importantly, for those who are more Western recruits and foreign fighters and the like, many of today's most vicious terrorists are actually working to undermine some of the brain's natural mechanisms that are anti-violent. Usually, you'd feel shame when you are committing violent acts, but some of today's terrorist groups will do things like have groups act of violence, so you feel connected to your band of brothers while you're doing that violent act, which absolves you from some of that shame mechanism.

Tim Farley: Is that like a warrior culture? It sounds like-

Leanne Erdberg: Yes.

Tim Farley: Killing is justified in a matter of war because, now, you are fighting a war.

Leanne Erdberg: I think that's precisely it. People don't like to do things that they don't already believe in, and so understanding that self-fulfilling prophecy, I think a warrior culture is exactly one of the ways in which terrorist groups today are able to have their individuals feel like their violence is always justified.

Tim Farley: Leanne, it seems to me, and at the risk of just grabbing a convenient phrase, that gas-lighting is a part of this. That is that there is a re-definition, if you will, of the society that the person grew up in and maybe not being truthful about it, or definitely not being truthful about it, but painting it as the individual being a victim of a society that rejected him or her.

Leanne Erdberg: I think there's a lot there. I think that there are real and perceived grievances, and victim-hood is an incredibly strong manifestation in the brain. I had learned that threats against your identity are processed in the same part of your brain as threats against your person, and so feeling like a victim is an incredibly powerful, emotional response. I think terrorists over-promise and under-deliver, and that's why there's actually so many defections over time in a lot of these groups, but, in that moment, they are able to capitalize on twisting a victim narrative into an incredibly empowering narrative.

Tim Farley: You mentioned the groups that you're working with trying to get to the heart of this, and I wonder, how do you do that? Do you talk to former terrorists? Do you say, "What made you go here," or are there more clinical tests that can be made? How do you investigate this?

Leanne Erdberg: Talking to former terrorists is a great first step. There are a lot of different people from a lot of different walks of life who have defected and who have left terrorist groups, and understanding the reasons why they joined is incredibly important, but it only gets you part of the way because the reason why somebody says they joined many years after they did may not be an accurate representation of why they actually joined, and it doesn't always lead you to help understand why people would leave, and so we're also trying to study other types of nonviolent groups that have shared bonds, that have shared moral missions, things like non-violent resistance movements, and seen them as a positive alternative. Do you form bands of brothers for boycotts and sit-ins and the way of addressing grievances through legitimate democratic means?

Tim Farley: As we wrap up here, I just wanted to ask, Leanne, as parents maybe have rebellious teenagers, what's new about that, but there may be members of a family, and you wonder about the things that they're doing and how there's changes of behavior. Are there things to watch for? It's not like we're all looking for it, but if you see something, say something. What do we, as a society, as a culture, need to be watching for with our fellow Americans?

Leanne Erdberg: I think that feelings of exclusion and hopelessness and marginalization can happen even at the family level. That sounds like a broad description because I think that probably everybody has felt excluded or hopeless or marginalized at some small point, but trying to understand how to make those type of efforts to help get people out of those situations, first of all, is probably just good for communities and societies and families, in general, but it also could be a really helpful prevention perspective to try and help young people from seeing that the only answer to what feels like a very specific psychological situation doesn't have to be a violent group that over-promises and under-delivers.

Tim Farley: If people want to find the work you're doing and look more into it, where can they go?

Leanne Erdberg: They can go to USIP's website,, and also sign up for events at the U.S. Institute of Peace. We're often bringing really interesting people to the stage, such as former terrorists and neuroscientists. I also advocate for, which is a research network that USIP supports that's devoted to more research and empirical evidence on bio-extremism and terrorism.

Tim Farley: Leanne, I do appreciate you spending time with us on POTUS today. Thanks so much.

Leanne Erdberg: Thank you so much for having me.

Tim Farley: Leanne Erdberg is Director of Countering Violent Extremism at the U.S. Institute of Peace, CVE they call it. You can find her on Twitter, @USIP. That's the actual Twitter handle for the group, @USIP.

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