“Jihadi John,” the Islamic State militant targeted in a recent drone strike, had a degree in computer engineering from a U.K. university (Islamic State via EPA)

In the last 24 hours many prominent politicians and pundits have said that they don’t want Syrian refugees to enter the United States. For example, Gov. Chris Christie has said that he doesn’t even want 5-year-old Syrian orphans to come into the country. Almost half of the country’s governors have said that they will refuse to allow Syrian refugees to come to their states. The same pattern applies in Europe where, for example, members of the new Polish government are threatening to break European law by turning away refugees.

Many of these people claim that they don’t want to admit refugees because they fear some of them will commit violent terrorist crimes, like those that just took place in Paris.

Yet there’s a different group of people which also appears to be highly prone to violent extremism, which isn’t getting nearly as much attention. In a forthcoming book published by Princeton University Press, Diego Gambetta, a renowned sociologist at the European University Institute in Italy, and Steffen Hertog, an associate professor at the London School of Economics, provide a new theory for why it is that engineers seem unusually prone to become involved in terrorist organizations. The following post is based on their earlier article for the European Journal of Sociology.

Authorities say as many as 20 people may have been involved in the plot to attack Paris. Here's what we know about them so far. (Gillian Brockell/The Washington Post)

Engineers are much more likely to become fundamentalist terrorists

Gambetta and Hertog painstakingly gather together data on individuals belonging to a variety of terrorist groups in the Muslim world. Where they are able to get the data, it displays a compelling pattern – engineers are much more prone to become members of violent terrorist organizations.

More than twice as many members of violent Islamist organizations have engineering degrees as have degrees in Islamic studies. Nearly half of those terrorists who had degrees had degrees in engineering. Even if you make extremely generous assumptions, nine times as many terrorists were engineers as you would expect by chance. They find a similar pattern among Islamist terrorists who grew up in the West – fewer of these terrorists had college degrees, but even more of those who had degrees were engineers.

Significantly, Gambetta and Hertog find the opposite pattern among non-violent Islamic groups. In these groups, people with other degrees than engineering were over-represented.

Gambetta and Hertog also examine non-Islamic terrorist organizations, where they find that left-wing terrorists are likely to be humanities graduates rather than engineers, except in movements in Turkey and Iran. However, there is weak evidence that leaders of extreme right-wing groups in the U.S. may be more prone to be engineers than chance would predict.

This isn’t because engineers are technically skilled or belong to certain social networks

Gambetta and Hertog find that two possible explanations for why engineers are more likely to become terrorists don’t work. Some people might argue that terrorist groups want to recruit engineers because engineers have valuable technical skills that might be helpful, such as in making bombs. This seems plausible – but it doesn’t seem to be true.

Terrorist organizations don’t seem to recruit people because of their technical skills, but because they seem trustworthy. They don’t actually need many people with engineering skills. Many of the engineers in Hamas, for example, play administrative roles. Nor is the abundance of engineers explained by social networks (in which, for example, a couple of engineers might have been recruited initially, who would then recruit friends who would also be more likely to be engineers).

It seems that engineers are common in clusters of terrorists that sprang up independently from each other, suggesting that there is some underlying factor that makes engineers more likely to be militants.

Engineers are more likely to become terrorists because of mindset and lack of opportunity

Gambetta and Hertog find strongly suggestive evidence that engineers are more likely to become terrorists because of the way that they think about the world.

Survey data indicates that engineering faculty at universities are far more likely to be conservative than people with other degrees, and far more likely to be religious. They are seven times as likely to be both religious and conservative as social scientists.

Gambetta and Hertog speculate that engineers combine these political predilections with a marked preference towards finding clearcut answers. This preference has affinities with the clear answer that radical Islamist groups propose for dealing with the complexities of modernity: Get rid of it. They quote the famous right-wing economist Friedrich von Hayek, who argues that people with engineering training “react violently against the deficiencies of their education and develop a passion for imposing on society the order which they are unable to detect by the means with which they are familiar.”

Gambetta and Hertog suggest that this mindset combines with frustrated expectations in many Middle Eastern and North African countries, and among many migrant populations, where people with engineering backgrounds have difficulty in realizing their ambitions for good and socially valued jobs.

This explains why there are relatively few radical Islamists with engineering backgrounds in Saudi Arabia (where they can easily find good employment) and why engineers were more prone to become left-wing radicals in Turkey and Iran. A particular religiously fundamentalist ideology gives engineers a philosophy that is in tune with their mindset and an understanding of the world that helps make sense of their poor economic prospects.

Not all engineers are prone to become terrorists

If Gambetta and Hertog are right, they have found a reason why many more terrorists are engineers than one might expect based on chance. They have also identified a propensity that doesn’t rely on Islamist extremism. The combination of mindset and lack of opportunity might easily occur in other societies than the Middle East and North Africa.

Obviously, even if all Gambetta and Hertog’s arguments hold, only a tiny, tiny minority of engineers are likely to become radicalized terrorists.

In nearly all cases, engineers are ordinary people. Perhaps they are more likely to be conservative and religiously devout than people in other professions, but this is hardly cause for condemnation.

This logic, however, applies to other people than engineers. If we shouldn’t draw problematic generalizations about engineers based on a tiny minority, we plausibly shouldn’t be drawing problematic generalizations about refugees, or for that matter about Muslim residents of the U.S. or Europe.

It’s hard to imagine prominent politicians or pundits making frightening sounding warnings about the dangers of letting engineers walk among us. Yet it’s no more ridiculous, given the evidence, than their fearful statements about Syrian refugees.