I was already a big Fishman Fan (Fishfan?) before I read this book. He is the scholar whose work I turned to when I was unexpectedly put on the Iraq file - about a year before ISIL exploded on the scene in 2014. Back then his papers on "Zarqawiism" were all-important, necessary reading to get a grip on what was taking place. (Gee, why are they "breaking the walls"?)
This book puts Fishman's expertise on full display. Unfortunately, that means it's probably not for ISIL beginners. Rather, (and befitting its university press status) it is for those who have some background in the group and Islamist militancy/jihadist networks generally. Also, because of the sheer amount of information in the book, it is not a quick read. (McCant's "ISIS Apocalypse" or Burke's "The New Threat" would be a good place to start and a complementary read before this one.)
Nevertheless, for those who really want to know where ISIL came from, how it got to where it is, and where it may be headed, this book is essential. Fishman's overview highlights the movement's strengths, (networked resiliency, steadfast commitment to "remain" in whatever form) and weaknesses (a movement that values violence over wisdom is not stable) which give the reader a good understanding of what may be coming in the years ahead as the so-called Caliphate loses its territory.
The book ends on a pessimistic note - Fishman observes that the West focuses too much on ISIL's tactics and operations to see that it is actually losing ground, but that the focus on the crumbling Caliphate means we ignore just how big of a problem global jihadism has become. When Al Qaeda attacked US embassies in Africa in 1998, that movement was only around 200 self-consciously elite militants. Today, however, there are jihadist groups all over the world, with tens of thousands of followers. This remains an extremely small fraction of the world's Muslims population, but clearly there are more challenges ahead - all the more reason to read this excellent, nuanced book.