"War was our condition and our history, the place we had to live in." Martha Gellhorn, a legendary war correspondent, saw things clearly. But why did mankind resign itself to this hard truth? Because of the age-old competition for food and sex, of course. Azar Gat's monumental interdisciplinary study links the enduring institution of war to the evolutionary logic of the human condition. A magnificent (if ultimately fatiguing) synthesis of the relevant scholarship—including paleontology, anthropology, archeology, and the modern devils, political science and sociology—it firmly fixes the roots of war in the innermost depths of the human psyche. Adjudicating the competing paradigms of Hobbes and Rousseau, Gat awards the crown to the Englishman. Mankind has never been free of conflict, even in the remotest prehistory. There was no "golden age."
As with other animal species, access to mates and food are the primary measures of evolutionary success, and everything else on which historians focus (power, wealth, fame, prestige, etc.) arose to satisfy these primary criteria. Gat is critical of scholars who place too much emphasis on the secondary factors, thereby creating a false distinction between human conflict and that seen elsewhere in nature. In prehistory—the "hunter-gatherer" epoch lasting about 95% of the time homo sapiens sapiens have existed on earth—the extended family group was the primary social unit, and evolution decreed the primacy of kinship. With resource scarcity triggering acquisitive violence toward those outside the bounds of kinship, successful hunters/warriors naturally gravitated to the leadership of interrelated clans and tribes. As social units increased in size, these chiefs and "big men" accumulated a disproportionate share of the most valuable resources, i.e., food and women. As Gat makes clear, the violence of prehistory was decidedly "asymmetric"—ambushes, raids, and opportunistic murder as opposed to pitched battles, and the retaliatory...