Morals and camaraderie can overwhelm other motivations and drive fighters to extreme acts.


Why do people die fighting for a cause?

To beat your enemies, you must understand them intimately. And so anthropologist Scott Atran and his colleagues have spent the last 2 years interviewing Islamic State group fighters and their opponents on the front lines. For a study published yesterday in Nature Human Behavior, Atran, director of research at Artis International, a research institute based in Scottsdale, Arizona, and his research team personally talked with extremists in the field, whom they’d reached through local leaders. They also conducted online surveys with thousands of Spanish citizens in order to include a more pacific population. Science spoke with Atran, who also holds positions at the University of Michigan in Ann Arbor, the University of Oxford in the United Kingdom, and France’s CNRS in Paris, about his work. This interview has been edited for brevity and clarity.

Q: What makes someone willing to die fighting for a cause?

A: Well, lots of things, but what best predicted willingness to die on the battlefront was both devotion to a tight-knit group of comrades—fusion with them—and commitment to sacred values. But the values actually trumped the group, which may be the first time that was shown. Because most of the military sociology and psychology, at least since World War II, has said that will to fight is based on camaraderie and fighting for your buddies.

In September 2014, [then-President Barack] Obama’s national security director said the greatest mistake the U.S. made in Iraq was underestimating ISIS’s will to fight, and he said it was similar in Vietnam. And then he said will to fight is an imponderable, which is why we undertook this study.

Q: What are sacred values?

A: They are moral values. We’ve shown in lots of different contexts that sacred values are immune or resistant to material trade-offs. You wouldn’t sell your children or sell out your country or your religion for all the money in China. Another aspect is that they generate actions because they’re the right thing to do, so you’re not really worried about risks or rewards or cost or consequences.

Q: Giving up your life or family for an idea or belief seems irrational. Is it rational on another level?

A: Oh, yeah. [Charles] Darwin, in The Descent of Man, puzzled over heroism and martyrdom. He argued that if people are inspired by these virtues and can inspire others, that group will win out over other groups. And in fact, since World War II, if you look at insurgents and revolutionary groups, they on average beat out standard police and armies with up to 10 times more firepower and manpower, because those police and armies rely on standard material incentives and disincentives like pay, promotion, and punishment. These guys rely on commitment.

When we were talking to ISIS and PKK [the Kurdistan Workers’ Party, devoted fighters against ISIS], they just threw down the surveys asking about forces’ physical strength and said that has nothing to do with it—it’s all about what’s in your heart.

Q: Is any one of us capable of dying for a cause?

A: Human beings are inspired by belief in apparently absurd things. Religion or transcendental ideologies, for example. This leap of faith seems to inspire others to great things, and probably is the reason we were able to form large polities. We found people were willing to sacrifice their family for these things.

Think of the origins of the monotheistic religions. Abraham is ready to slit his son’s throat. The very term “Islam” means submission of tribal and genetic identities. So those things just grab the minds and hearts. We’ve also done [functional MRI] scans which aren’t published yet. Sacred values inhibit deliberative reasoning, so they’re in a sense more efficient in the clutch. You don’t even think about them.

Q: You found that devotion to a cause also intimidates opponents.

A: Oh, yes. When one group perceives the enemy as committed, they are even less likely to make sacrifices for their values. It has a paralysis effect. Of the almost 7000 Europeans we surveyed, a very small number behaved quite the opposite: The more they perceived the Islamic State as spiritually committed, the more they themselves became spiritually committed. We’re starting to work with [the Defense Advanced Research Projects Agency] and the U.S. Air Force to identify who in our own forces would be more likely to become devoted actors. Because those are the guys you want.

Q: Does this work have applications for policy or military strategy?

A: Decidedly. It would be useful for our politicians and pundits to realize that these people are not crazy, they’re not nihilists or brainwashed or losers. In fact, they argue that we’re the nihilists, because we have no moral values anymore.

Q: What’s it like interviewing terrorists?

A: I’ve interviewed many people who have done terrible things, including jihadis, white supremacists. And you’d be surprised how often they’re just nice guys. Normal people. How do you get into it? The best predictor is your friends.

Q: Does the work shed light on conflicts closer to home?

A: Sure. You find the same thing with pro-life and pro-choice and gun rights. And these xenophobic ethno-nationalist groups, they’re getting a lot of young people motivated by sacred values and group fusion. Where recruits are on this path to extreme behavior is very important. What works to dissuade people when they’re at the beginning, when you can use jobs or sex or whatever, usually backfires when they’re locked in.

Q: Is there any recourse once people are locked in?

A: Yes, it’s to understand it, and then figure out how values can be so inspiring for open societies as well. Look at the American Revolution. [Thomas] Jefferson, in his original draft of the Declaration [of Independence], put, “We hold these truths to be sacred.” 

For more on what motivates humans to kill, see this conversation with Scott Atran and other experts.