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The violent actions of a few extremists can alter the course of history, yet there persists a yawning gap between the potential impact of these individuals and what we understand about them. In Engineers of Jihad, Diego Gambetta and Steffen Hertog uncover two unexpected facts, which they imaginatively leverage to narrow that gap: they find that a disproportionate share of Islamist radicals come from an engineering background, and that Islamist and right-wing extremism have more in common than either does with left-wing extremism, in which engineers are absent while social scientists and humanities students are prominent. Using rigorous methods and several new datasets, they explain the link between educational discipline and type of radicalism by looking at two key factors: the social mobility (or lack thereof) for engineers in the Muslim world, and a particular mindset seeking order and hierarchy that is found more frequently among engineers. Engineers´ presence in some extremist groups and not others, the authors argue, is a proxy for individual traits that may account for the much larger question of selective recruitment to radical activism.

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"That´s really good work, and they deserve credit for that observation. It is thrilling and intriguing as a theoretical issue."--Jeffrey I. Victoroff, University of Southern California Keck School of Medicine, Chronicle of Higher Education

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Diego Gambetta is professor of social theory at the European University Institute, Florence, and official fellow of Nuffield College at the University of Oxford. His books include The Sicilian Mafia and Codes of the Underworld (Princeton). Steffen Hertog is associate professor of comparative politics at the London School of Economics. He is the author of Princes, Brokers, and Bureaucrats.

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