I was most impressed by the years of rolling surveys, structured by cutting-edge social science theory and insight, to support the bookâs central argument on the sense of personal and collective significance that ISIS initially afforded Sunni Arabs in the aftermath of America's intervention in Iraq and then squandered through brutal intolerance. The focus on Iraq as the cradle of this violent and dynamic transnational movement, and on local folk in search of meaning and certainty in their lives as opposed to more current journalistic preoccupation with foreign volunteers and the role of ideology, is key to making this book the best empirical work that I have seen on the rise and demise of ISIS.