If you want a book that brings the fruit of vast experience in the geopolitical dimensions of the Middle East, this is it: And Then All Hell Broke Loose: Two Decades in the Middle East (Simon & Schuster, 2016). The author is Richard Engel, long time chief foreign correspondent for NBC news. Engel brings a perspective built on decades covering the Middle East. He also brings a historic view of the region that includes centuries of development. This book is a salve against reductionists who offer simple explanations not anchored in actual history.
The twenty pages of introduction boil down long complex eras into understandable narratives that shed light on why Iraq has been divided into its several religious/ethnic sections since the Europeans carved up the Middle East following WW I. He elegantly clarifies just why Al Qaeda-become-ISIS did not move into Iraq in league with Saddam; quite to the contrary, secular dictator Saddam repulsed and repressed all religious fundamentalist movements. No, they came and come to repel the American invasion and occupation, simple as that.
If there is one book with which you can educate yourself about this region through the past thousand years, this might be it. That is certainly the case for me. Only a voice of realism and experience can write:
“For twenty years I saw the big men at their prime, and chronicled their downfall and the mayhem that followed…I suspect a new generation of big men will return. No people can tolerate chaos forever. Dictators will offer a way out and many of the exhausted and brutalized people of the Middle East will accept them, and I suspect Washington will as well.”