Why do people become violent extremists? You might speculate that the answer is poverty. George W. Bush thought so: “We fight against poverty because hope is an answer to terror.” Or you might think a lack of education explains it. Laura Bush thought so: “A lasting victory in the war against terror depends on educating the world’s children.”
Neither of these answers is correct, however. Most extremists, including those who commit violence, are not poor and do not lack education.
Suicide bombers are likely to have more income and more education than most people in their home nation, research shows. A few years after the attacks of Sept. 11, people in Jordan, Morocco, Pakistan and Turkey with higher than average incomes were no less likely to say that suicide attacks against Westerners were justified. People with more education were actually more likely to reach that conclusion.
Similarly, among Palestinians, support for violence against Israeli targets is pervasive — not lower among people with relatively high earnings and education than it is among those who are illiterate and unemployed.
In light of these findings, Princeton economist Alan Krueger says: “To understand who joins terrorist organizations, instead of asking who has a low salary and few opportunities, we should ask: Who holds strong political views and is confident enough to try to impose an extremist vision by violent means?” That’s the right question. And at least part of the answer comes from social dynamics, as illuminated by some old, and seemingly far afield, experiments in group psychology.
The original experiments, conducted in 1961 by James Stoner, a graduate student at the Massachusetts Institute of Technology, worked as follows. A number of Americans were assembled into groups and asked whether they would like to take certain hypothetical risks — to try a new job, to invest in a foreign country, to escape from a prisoner-of-war camp, or to run for political office. As it turned out, participation in group decision-making made people more inclined to take such risks. Stoner’s findings were later replicated by many others, leading to the conclusion that when people act in groups, they experience what Stoner called a “risky shift.”
But later studies drew this conclusion into serious question. Answering many of the same questions on which Americans displayed a risky shift, citizens of Taiwan displayed a shift toward greater caution. How come?
Everything depends on the group members’ original inclinations. When people are initially disposed toward risk-taking, their discussions lead them further in that direction. When people are initially disposed toward caution, their discussions make them more cautious still. While the Americans started out risk-inclined, the Taiwanese started out risk-averse, and that simple difference explained the opposing shifts.
In short, groups tend to polarize. On political issues, group polarization occurs every day.
In France, for example, group members who start out suspicious of the United States become even more so after they exchange points of view. If people are inclined to want to punish some wrongdoer, their discussions with one another tend to lead them to favor a more severe punishment. Likewise, people with radical tendencies become more radical after group discussion — and more willing to favor breaking the law.
Why does group polarization occur? The first answer involves information. Suppose that most group members begin by thinking that some religious group, leader or nation is evil. If so, they will hear a lot of arguments to that effect. As they absorb them, they will be inclined to move toward a more extreme version of their initial judgment.
People also care about their reputations, so some group members will adjust their positions in the direction of the dominant view. A disturbing implication is that if group members listen only to one another, and if most of them have extremist tendencies, the whole group might well march toward greater radicalism and even brutality.
Writing in 1998, Russell Hardin, a political scientist at New York University, drew attention to the “crippled epistemology of extremism,” by which he meant to emphasize how little extremists know. Focused on Islamic fundamentalists, Hardin was concerned about what happens “when the fanatic is in a group of like-minded people, and especially when the group isolates itself from others.”
In the years ahead, the international effort to combat violent extremism will sometimes require force, and it will sometimes require economic pressure. But it will succeed only if it disrupts recruitment and radicalization by enclaves of like-minded people.
Cass R. Sunstein, the former administrator of the White House Office of Information and Regulatory Affairs, is a professor at Harvard Law School and a Bloomberg View columnist.