Robert O'Connell writes about the large sweep of war from the ancient Egyptians to the present day. I think his analysis is sometimes muddled, but he writes well and he sometimes has flashes of creativity that are startling. He has ideas that are very powerful and I appreciate the effort he puts in to try to say something new. Like an Irishman improvising wildly on a fiddle: some of the attempts don't work out, but some of the trills and flourishes are arresting, original and amazingly insightful.
For example: O'Connell argues that war is a continuum of activities that have swung back and forth (like a pendulum) throughout history. At one extreme is the courtly, rule-bound, honor-driven combat of the knightly period in European history: dropped handkerchiefs, pauses to allow one's opponent to regain his saddle, and flowery compliments to the defeated. At the other is the win-at-all costs, slaughter-them-all combat of the Mongols in the 1220s. (Genghiz Kahn once killed all the inhabitants of a city except for a select handful. These he kept alive and after his troops had withdrawn from the city, he allowed them to go from street to street calling out that the Mongols were gone. Once people came out of hiding, his troops came storming back in, killed them all, and the handful he had kept alive to call them out of hiding were killed as well.) Over time warfare in different parts of the world has resembled first one end of the spectrum, then the other. [One of the reasons it is so difficult to come up with a single definition of what war is, is that the kind of activity it is has swung back and forth over time and across regions.]
Very though-provoking. Recommended.