His chapters are entitled
I'll give him this. He makes some interesting points. For example, he claims that Clausewitz had it backwards when he asserted that war is a continuation of politics by other means. Having worked for a political campaign I agree: politics is really a continuation of war by other means. He also states the obvious - in order to have a war, you need an enemy. This point was explored more fully by another psychiatrist, Anthony J. Stevens, in his book, The Roots of War: A Jungian Perspective in which discusses enemy-making as pseudospeciation, the portrayal of the enemy group as less than, or at least other than, human. Stevens also delves into the pervasiveness of war-metaphors in our culture, which Hillman merely decries.
With regard to his attack on Christianity, Hillman would do well to read Thomas Cahill's Gifts of the Jews: How a Desert Tribe of Nomads Changed the Way Everyone Thinks and Feels. That is to say, most of what he identifies with Christianity is what Christianity inherited from Judaism. That he attacks it might tempt me to brand him as an anti-Semite, but there is a better designation. I think he may be an Occidentalist, as described by Buruma and Margalit in their book, Occidentalism: The West in the Eyes of Its Enemies, or perhaps a Bourgeoisophobe, to use David Brook's designation.
All in all, I think much of what Dr. Hillman says in this book is said with more regard for its effect rather than for its accuracy. For example, he quotes a well-known hymn:
Onward Christian soldiers,
Marching off to war,
Sorry, James. It's "Marching as to war," and that makes all the difference. If my impression its statements being made for effect over accuracy is correct, then A Terrible Love of War might fall into the category of discourse studied by Dr. Harry G. Frankfurt in his treatise, On Bullshit.