One approach to understanding the reasons for warfare is to study deep history.
Archaeology, anthropology, ethnohistory, and related disciplines provide great time depth for studying war. They also provide information on how and why warfare took place in a wide array of cultures. Yet this highly relevant information is often ignored. Most political scientists and historians who consider the reasons for warfare start with the modern era, or even the 1800s; fewer go back to the ancient Greeks. And almost all consider only the cultures of Europe and other state-level societies such as China. Click
If we ever hope to end warfare we must first understand why it occurs. Because this is trivially obvious, it is surprising how poorly studied warfare is. Considerable work has been done on the details of particular wars and the events leading up to them, but little has been done to find the underlying reasons for warfare in general. My colleague Kevin Hill and I recently undertook a brief survey of courses on warfare taught at fifteen major research universities. We found numerous courses on specific wars, eighteen on the concepts and methods of war, and only six that we could construe as examinations of the general causes of warfare - and even those were based in a single discipline.
This lack is probably due in part to our approach to social problems in general. Most people tend to think that common sense is adequate for solving them. But we abandoned the commonsense approach to problems in physics and biology long ago, with the result that we have made great progress in these sciences. Despite its obvious importance, there has been little application of the scientific method of hypothesis, comparison, and testing to unearthing the causes of warfare.
One approach to understanding the reasons for warfare is to study deep history. Archaeology, anthropology, ethnohistory, and related disciplines provide great time depth for studying war. They also provide information on how and why warfare took place in a wide array of cultures. Yet this highly relevant information is often ignored. Most political scientists and historians who consider the reasons for warfare start with the modern era, or even the iSoos; fewer go back to the ancient Greeks. And almost all consider only the cultures of Europe and other state-level societies such as China. These studies are relevant, but they are too limited to exhibit general patterns over the entire span of human history and prehistory. Discerning whether or not human warfare has a genetic base, for instance, is an impossible task to accomplish with such limited scope; instead, we must examine evidence from deep history and worldwide ethnography, which represent most of human history and most of human cultural variability.
The global study of warfare is necessary to determine whether war has a single cause or many different causes. If the causes of war have varied over time, then we must discern how and why this is the case. Prima facie, it appears that some modern wars, particularly in the West, are different from wars before the twentieth century, whereas recent regional wars in Africa and Asia appear to have the same causes as ancient wars. If significant changes in the nature of warfare took place in the modern era, knowing how and why such changes arose is necessary for understanding modern wars.
One problem with studying warfare is how to define it. Use of such criteria as the presence of standing armies and professional soldiers eliminates consideration of warfare during most of human history. On the other hand, including homicide and intragroup feuding, while relevant to the study of violence, makes the study of war difficult because it mixes behaviors that have very different causes.
Definitions of war must not be dependent on group size or methods of fighting if they are to be useful in studying past warfare. One productive approach is to view warfare simply as socially sanctioned conflict between independent groups or polities. This enables us to include warfare in all types of human societies throughout history.
Quite a bit is known about warfare in the deep past, and about warfare in nonstate societies that have not been affected by nation-states. One obvious conclusion is that warfare was frequent long before complex societies developed. This generalization is clearly established by Lawrence Keeley in War Before Civilization, and was also discussed recently by Richard Wrangham and Raymond C. Kelly.1
Such warfare was chronic, virtually annual. Few societies experienced even one generation without significant warfare. Regardless of its frequency, almost all societies lived in fear of attack. Great efforts, often at considerable costs, were made to live in protected places - such as on the tops of windswept hills and on the faces of cliffs far from water supplies - and to build fortifications. Some groups lived in settlements that were larger or more compact than optimum, simply for defense. The deadliness of war made these measures inevitable. Estimates of around 25 percent of males dying from warfare are derived for virtually all continents, for foragers and egalitarian farmers alike. The probability of dying as a result of warfare was, in fact, much higher in the past than it is today.
Even those few societies described as peaceful were neither inherently nor historically peaceful. For example, archaeological evidence now shows that the SaIishian tribes of the Plateau area of western North America, who had no remembered history of warfare when studied by anthropologists in the nineteenth and early twentieth centuries, had had significant warfare a few centuries earlier. One class of so-called peaceful societies consists of those that underwent demographic collapse and radical subsistence deprivation as the result of Western expansion. This is an important group from whom we can learn a great deal about the causes of warfare and of peace, but they do not provide evidence for societies that have learned to avoid war. Other so-called peaceful societies are foragers who have become symbiotic with nearby farmers, such as the Pygmies of Central Africa or the Semang of Malaysia. In both cases, the farmers fight intensively with each other while the foragers stand by outside of the conflict. Again, this is not proof of inherently peaceful societies.