Any biological anthropologist opining about human behavior is required by long-established tradition to note that for 99 percent of human history, humans lived in small, stable bands of related hunter-gatherers. Game theorists have shown that a small, cohesive group is the perfect setting for the emergence of cooperation: The identities of the other participants are known, there are opportunities to play games together repeatedly (and thus the ability to punish cheaters), and there is open-book play (players can acquire reputations). And so, those hunter-gatherer bands were highly egalitarian. Empirical and experimental data have also shown the cooperative advantages of small groups at the opposite human extreme—namely, in the corporate world.
But the lack of violence within small groups can come at a heavy price. Small homogenous groups with shared values can be a nightmare of conformity. They can also be dangerous for outsiders. Unconsciously emulating the murderous border patrols of closely related male chimps, militaries throughout history have sought to form small, stable units; inculcate them with rituals of pseudokinship; and thereby produce efficient, cooperative killing machines.
Is it possible to achieve the cooperative advantages of a small group without having the group reflexively view outsiders as the Other? One often encounters pessimism in response to this question, based on the notion that humans, as primates, are hardwired for xenophobia. Some brain-imaging studies have appeared to support this view in a particularly discouraging way. There is a structure deep inside the brain called the amygdala that plays a key role in fear and aggression, and experiments have shown that when subjects are presented with a face of someone from a different race, the amygdala gets metabolically active—aroused, alert, ready for action. This happens even when the face is presented subliminally, which is to say, so rapidly that the subject does not consciously see it.
More recent studies, however, should mitigate this pessimism. Test a person who has a lot of experience with people of different races, and the amygdala does not activate. Or, as in a wonderful experiment by Susan Fiske, of Princeton University, subtly bias the subject beforehand to think of people as individuals rather than as members of a group, and the amygdala does not budge. Humans may be hardwired to get edgy around the Other, but our views on who falls into that category are decidedly malleable.
In the early 1960s, a rising star of primatology, Irven DeVore, of Harvard University, published the first general overview of the subject. Discussing his own specialty, savanna baboons, he wrote that they “have acquired an aggressive temperament as a defense against predators, and aggressiveness cannot be turned on and off like a faucet. It is an integral part of the monkeys’ personalities, so deeply rooted that it makes them potential aggressors in every situation.” Thus, the savanna baboon became, literally, a textbook example of life in an aggressive, highly stratified, male-dominated society. Yet in my observation of Forest Troop, I saw members of that same species demonstrate enough behavioral plasticity to transform their society into a baboon utopia.
The first half of the twentieth century was drenched in the blood spilled by German and Japanese aggression, yet only a few decades later it is hard to think of two countries more pacific. Sweden spent the seventeenth century rampaging through Europe, yet it is now an icon of nurturing tranquility. Humans have invented the small nomadic band and the continental megastate and have demonstrated a flexibility whereby uprooted descendants of the former can function effectively in the latter. We lack the type of physiology or anatomy that in other mammals determines their mating system and have come up with societies based on monogamy, polygyny, and polyandry. And we have fashioned some religions in which violent acts are the gateway to paradise and other religions in which the same acts consign one to hell. Is a world of peacefully coexisting human Forest Troops possible? Anyone who says “No, it is beyond our nature” knows too little about primates, including ourselves.
HOPE ON THE BATTLEFIELD
Dave Grossman
DURING WORLD WAR II, U.S. Army Brigadier General S. L. A. Marshall asked average soldiers how they conducted themselves in battle. Before that, it had always been assumed that the average soldier would kill in combat simply because his country and his leaders had told him to do so and because it might be essential to defend his own life and the lives of his friends. Marshall’s singularly unexpected discovery was that of every 100 men along the line of fire during the combat period, an average of only 15 to 20 “would take any part with their weapons.” This was consistently true, “whether the action was spread over a day, or two days, or three.”
Marshall was a U.S. Army historian in the Pacific theater during World War II and later became the official U.S. historian of the European theater of operations. He had a team of historians working for him, and they based their findings on individual and mass interviews with thousands of soldiers in more than 400 infantry companies immediately after they had been in close combat with German or Japanese troops. The results were consistently the same: only 15 to 20 percent of the American riflemen in combat during World War II would fire at the enemy. Those who would not fire did not run or hide—in many cases, they were willing to risk greater danger to rescue comrades, get ammunition, or run messages. They simply would not fire their weapons at the enemy even when faced with repeated waves of banzai charges.
Why did these men fail to fire? As a historian, psychologist, and soldier, I examined this question and studied the process of killing in combat. I have realized that there was one major factor missing from the common understanding of this process, a factor that answers this question and more: the simple and demonstrable fact that there is, within most men and women, an intense resistance to killing other people—a resistance so strong that in many circumstances, soldiers on the battlefield will die before they can overcome it.
Indeed, the study of killing gives us good reason to feel optimistic about human nature, for it reveals that almost all of us are overwhelmingly reluctant to kill a member of our own species under just about any circumstance. Yet this understanding has also propelled armies to develop sophisticated methods for overcoming our innate aversion to killing, and as a result, we have seen a sharp increase in the magnitude and frequency of posttraumatic response among combat veterans. Because human beings are astonishingly resilient, most soldiers who return from war will be fine. But some will need help coping with memories of violence. When those soldiers return from war—especially an unpopular one like Iraq—society faces formidable moral and mental health challenges in caring for and reintegrating its veterans.
RESISTANCE TO KILLING
S. L. A. Marshall’s methodology has been criticized, but his findings have been corroborated by many other studies. Indeed, data indicate that soldiers throughout military history have demonstrated a strong resistance to killing other people.
When nineteenth-century French officer and military theorist Ardant du Picq distributed a questionnaire to French officers in the 1860s, he became one of the first people to document the common tendency of soldiers to fire harmlessly into the air simply for the sake of firing. One officer’s response stated quite frankly that “a good many soldiers fired into the air at long distances,” while another observed that “a certain number of our soldiers fired almost in the air, without aiming, seeming to want to stun themselves.”