Very much in the genre of the work of British authors John Keegan, Richard Holmes, and others that explores the grim essence of warfare. The author, an army infantry officer who has taught psychology at West Point, writes well and persuasively. Historians, however, will stir uneasily as they examine his footnotes, which cite sources from Soldier of Fortune magazine to the surveys of S. L. A. Marshall to various popular works of history. Grossman acknowledges this limitation and presses on, marshaling an impressive range of anecdotes, which he then turns into a psychological theory illustrating killing-response stages with flow charts and diagrams. The book concludes with a troubling discussion of the progressive desensitizing of American youth to killing: it is something of a tangent to the central argument, but powerfully put nonetheless. A flawed but intriguing study.