War in Human Civilization Book

In War in Human Civilization, Azar Gat tackles two major questions about war. First, what are the essential reasons why humans fight wars? Second, how have the motivations, practices, and lethality of war changed as human civilization has transformed over time? Although the book is a challenging read given its length and dense writing, Gat offers much illumination on these and other questions.
Gat received his Ph.D in history and he now teaches political science at Tel Aviv University. War in Human Civilization reflects his interdisciplinary career by employing ideas and methods from a variety of science and social science disciplines. Gat needs this expansive toolkit because his essential questions cross disciplinary lines and many of his topics cannot be accessed with only the standard methods of history and political science.
The book moves chronologically through different stages of humanity's natural and cultural evolution. Gat begins with hunter-gatherers and proceeds to the development of tribes, agriculture, chieftainships, states, and ultimately modern forms of politics, economics, and warfare. The examination of hunter-gatherers is especially crucial in establishing his thesis. He grants great significance to hunter-gatherer warfare because Homo sapiens has spent the vast majority of its existence in this mode and the evolutionary mechanisms we developed in this state of nature still deeply influence our behavior today. Employing insights from archaeology, animal behavior, and modern observations of hunter-gatherers, Gat shows that hunter-gatherers used violence to steal women, kill male competitors and their offspring, and access crucial resources and territory.
During his discussion of hunter-gatherer warfare, Gat presents his thesis: the essential reason why humans fight wars is to obtain and/or protect access to food and sex, what he calls an evolutionary motivational complex. Gat believes that violence is "innate, but optional," meaning that human beings have evolved mechanisms to facilitate the use of violence but that violence is not an inevitable product of our evolutionary heritage (36). Rather, violence is one of many tactics humans can employ to satisfy the evolutionary complex, and humans will deploy more or less violence depending upon a variety of factors.
This last point leads us to Gat's second major objective: to explain how changes in human civilization have transformed warfare throughout recorded history even though the essential motivation for violence has not changed. Gat shows how key developments in human cultural evolution, such as agriculture, states, and industrial production, transformed the ways those societies fought. For example, he shows how the development of gunpowder, ocean navigation, and the printing press in the 15th century triggered a tangle of interconnected developments that heralded the start of modernity: centralized state authority, infantry centered armies, urbanism, the "commercial-financial revolution," and nationalism (480).
Gat maintains that throughout the cultural evolution of warfare violence has remained instrumental to human goals rather than an end in itself. He posits that human beings will be more or less violent based on the utility of violence in achieving basic evolutionary goals in different civilizational conditions. In this vein, he concludes that the frequency and relative lethality of wars has declined in the past few centuries not just because of democratization and shifting values, but because the incentives for using war have lessened under modern civilizational conditions. These conditions include nuclear weapons, global trade, and reduced tie between force and wealth procurement in the industrialized world.
Gat's book is highly successful in addressing the questions of why humans fight wars and how war has evolved. One of his greatest strengths is his ability to break down false dichotomies that have obscured debates about the motivations behind human violence. The most important of these is the debate between social constructionist and biological frameworks. Gat shows that social constructs over which people may fight are derivative of and subordinate to the central objectives of the evolutionary complex. Humans pursue wealth or political power, for instance, ultimately because they consciously or unconsciously want to secure access to food and reproduction. Achieving wealth or power are means to those ends. Political authority, ideologies, and wealth may be constructed differently in different societies with deeply important consequences for scholars, but these constructs rest on a "deep core of innate human propensities and predispositions, which represent evolution-shaped basic needs" (422). Future debates on the riddles of war will be far more productive if they follow Gat's lead in synthesizing "nature and nurture" rather than putting them in a false rivalry.