War: What is it good for? (13 page)

The Cage

Another map will help us answer this new question.
Figure 2.3
shows the same ancient empires as
Figure 2.2
but with some extra details added. The areas marked in gray show the agricultural heartlands where humans first invented farming, in the years between about 10,000 and 5000
B.C.
The beginning of farming was one of the two or three real turning points in human history, and I described it in some detail in my book
Why the West Rules—for Now;
I return to it here, though, because of the coincidence between the places where farming began and the places where ancient empires appeared several thousand years later. The reason that war gave birth to Leviathan in these lucky latitudes, while life outside them remained as poor, nasty, and brutish as ever, is that farming made war productive.

The story begins about nine thousand years before the Persians and Greeks fought at Plataea, when the world began warming up after the last
spasm of the Ice Age.
²
Plants and animals, including humans, reproduced madly. At the coldest point in the Ice Age, twenty thousand years ago, there had been barely half a million people on earth; ten thousand years later, there were ten million.

Then as now, global warming affected every part of the planet but affected some parts more than others. What made the lucky latitudes lucky was that in this part of the world, climate and ecology conspired to favor the evolution of large-grained grasses and big, meaty mammals. The hunting and gathering were better here than anywhere else on earth, and of the ten million people in the world of 8000
B.C.
more than half lived in the lucky latitudes.

During the ice ages, humans had spent their time in tiny bands of foragers, but even before the Ice Age had completely finished, the pickings were so good in some parts of the lucky latitudes (particularly, it seems, the Jordan Valley) that people settled in permanent villages, feeding year-round from the newly abundant food sources. As they did so, a remarkable thing happened. By cultivating and tending plants and animals, humans unconsciously exerted selective pressures that modified these food sources' genetic structures. This process—domestication
³
—happened first in the lucky latitudes, because they had by far the densest concentrations of potentially domesticable plants and animals on earth.

Jared Diamond makes the point well in his classic study
Guns, Germs, and Steel
. The world, Diamond observes, has roughly 200,000 species of plants, but humans can only eat about 2,000 of these, and only about 200 have much genetic potential for domestication. Of the 56 plants with edible seeds weighing at least ten milligrams, 50 originally grew wild in the lucky latitudes, and just 6 in the whole of the rest of the planet. Of the fourteen species of mammals weighing over a hundred pounds that humans domesticated before twentieth-century science kicked in, nine were natives of the lucky latitudes.

No surprise, then, that domestication began in the lucky latitudes, nor
that within the lucky latitudes it appeared first in southwest Asia, which had the densest concentrations of potential domesticates of all. The first signs of this process (the appearance of unnaturally large seeds and animals, which archaeologists usually call “cultivation”) show up in the Hilly Flanks between 9500 and 9000
B.C.
, and full-blown domestication is evident by 7500.

What we now call China had high concentrations of domesticable plants and animals too, but not as high as the Hilly Flanks. Between the Yellow and the Yangzi Rivers rice was being cultivated by 7500
B.C.
and domesticated by 5500. Millet and pigs followed over the next millennium. In Pakistan, barley, wheat, sheep, and goats were cultivated and then domesticated on roughly the same schedule. Squash, peanuts, and teosinte (the ancestor of corn) were being cultivated in Mexico by 6500 and had been domesticated by 3250, and quinoa, llamas, and alpacas in Peru by 6500 and 2750 (
Table 2.1
, on page 88). The fit between the density of potential domesticates and the date at which domestication began is almost perfect.

Domestication was a long, drawn-out process, and with every passing year a little bit more of the wild was planted and a few more fields were weeded, hoed, plowed, watered, and fertilized. Farming had its costs—farmers typically worked more than foragers and ate more monotonous, less healthy diets—but it had one huge attraction: it produced much more food from an acre of land. As the food supply grew, humans in the lucky latitudes did what every animal does in such circumstances, turning the extra calories into more of themselves, and the lucky latitudes began looking more and more peculiar. In the rest of the world, wandering hunter-gatherers were spread thinly across the land, typically at densities of less than one person per square mile. By the first millennium
B.C.
, however, some parts of the lucky latitudes had hundreds of farmers packed into every square mile.

The population explosion set off cascades of unintended consequences. One was that farming spread: as the best land in the original agricultural cores filled up, farmers boldly went where no peasant had gone before, seeking out fertile fields beyond the horizon. Within four thousand years prehistoric frontiersmen had vaulted from the westernmost core of domestication in the Hilly Flanks as far as the Atlantic coast of France, and from the easternmost core between the Yellow and Yangzi River valleys as far as Borneo.

Another unintended consequence was that as agriculture pushed up
population densities, people found more reasons to fight. This was not, however, because farming itself directly caused more war; from Helen of Troy to the War of Jenkins's Ear,
⁴
men have contrived to kill each other over almost anything that can be imagined, with property, prestige, and women taking the top places on the list. But cramming more bodies into the same landscapes (rather like cramming more lab rats into the same cage) simply meant there were more people to fall out with and more to fall out over.

The consequence of crowding that matters most for the story in this book, though, was what defeat began to mean for fighting farmers. Gradually, over the course of millennia, it became clear that losing a conflict in a settled, crowded agricultural landscape was a very different proposition from losing one in a fluid, fairly empty landscape of foragers.

Take, for instance, the story of ≠Gau,
⁵
a San hunter in the Kalahari Desert. Sometime in the 1920s or '30s, ≠Gau fell out with another hunter, Debe, over bush food. ≠Gau, a hothead, speared Debe, killing him. Debe's angry family then attacked ≠Gau, but in the struggle that followed, ≠Gau killed again, shooting a man in the back with a poisoned arrow. Realizing he had gone too far, “≠Gau grabbed his people and left the area” (the words of another San, telling the story in the 1950s). A posse pursued ≠Gau, but after a skirmish that cost three more lives, the San storyteller said, “≠Gau and his group ran away.” Among hunters and gatherers, when the going got tough, the tough simply got going. So long as there was room to keep moving, no one could make ≠Gau pay for his crimes. (≠Gau ultimately came to a fittingly violent end, speared through the heart by a young man from his own group.)

How different the fate of farmers who lose fights. In 58
B.C.
, Julius Caesar tells us, a farming tribe called the Helvetii abandoned their home in what is now Switzerland and migrated into Gaul to find better land. Gaul, as they knew, was full; all the good farmland had been settled long ago. But the Helvetii did not care. They would simply take what they wanted, beginning with the lands of the Aedui tribe.

What were the Aedui to do? One option was to sit out the storm and hope for the best, but the best was not looking good. As soon as the Helvetii arrived, Caesar says, the Aedui found “their earth scorched, their children enslaved, and their towns stormed.” The fruits of doing nothing promised to be death, ruin, and bondage.

A second option was to fight back, but given that “the Helvetii exceed the other Gauls in ferocity, because they are embroiled in almost daily battles with the Germans” (Caesar's words again), many Aedui found that an alarming prospect. The necessary experience and organization, they felt, could not simply be plucked out of thin air. Others among the Aedui, though, were very keen on fighting. A certain Dumnorix (“highly audacious, extremely influential … and ambitious for revolution,” says Caesar; he sounds like a Gallic version of ≠Gau) had raised a private force of horsemen. He planned to use the crisis to overthrow the ineffective Aeduan aristocracy and make himself king, turning the Aedui into a regional power.

A third possibility, the one the Aedui actually chose, was to put themselves under the protection of powerful friends. This, however, was anything but straightforward. To most Aeduans, the obvious friend was Caesar, the newly appointed governor of the neighboring Roman province. Dumnorix, however, was playing a double game; far from reorganizing Aeduan society to fight off the Helvetii, he actually planned to put the Aedui under Helvetian protection. The Helvetii would then help him become king, and together the two tribes would dominate Gaul and keep Rome out.

The one option the Aedui did not have was to run away and start over, like ≠Gau and his people in the Kalahari Desert. ≠Gau's band had relatively little to lose by decamping, but the Aedui would lose everything. Farmhouses, fields, and stored food would be forfeited; generations' worth of ditch-digging, well-sinking, terrace-building, and brush-clearing would be wiped away. And where, in any case, would they go? They were surrounded by other farming groups—Boii, Arverni, Allobroges—and if the Aedui moved, they would find themselves in just the same position as the Helvetii, attacking another tribe to steal its land.

The crowding that farming created in the lucky latitudes was one of the most important things that has ever happened to humans—so important, in fact, that not one but two enterprising social scientists have tried to claim ownership of the idea by thinking up a clever name for it. Back in 1970, the anthropologist Robert Carneiro wrote a paper about it in the journal
Science,
calling it “circumscription,” and in 1986 the sociologist Michael Mann rebranded it as “caging.”

The important thing about circumscription/caging, Carneiro and Mann argued, is that the people it traps find themselves forced—regardless of what they may think about the matter—to build larger and more organized societies. Unable to run away from enemies, they either create a more effective organization so they can fight back or are absorbed into the enemy's more effective organization.

The Aedui are a perfect example. Because they had nowhere to hide, only three outcomes were really possible in 58
B.C.
They could end up being dominated by the Helvetii; the Aedui and Helvetii could get together, forming a single society that would dominate Gaul; or the Aedui, the Helvetii, and everyone else in Gaul could end up dominated by the Romans (which is what happened). From the Aeduan perspective, the three outcomes had very different levels of desirability, but seen in a broader perspective, they all led to basically the same result. Someone—Dumnorix, the Helvetian aristocracy,
⁶
or Caesar—would become a stationary bandit in Gaul. A single larger society would be formed, with either a king, a clique of warriors, or a Roman governor providing stronger government than the old tribal aristocracies had. And last but not least, Leviathan—in the interests of having a nice, well-behaved population to tax—would stamp out the intertribal feuds that made Gaul such a violent place.

Mann's label, caging, strikes me as the best name for this process. Ever since humans had evolved, they had been killing each other in quarrels. In the short term men like ≠Gau might profit handsomely from fighting, but in the long term their violence was unproductive. It was just the background noise of
Lord of the Flies
. Only when climate change generated farming and sent people in the lucky latitudes down the road toward caging could war become productive, with winners incorporating losers into larger societies.

Of all the places in this book where words might cause discomfort, labeling war in the lucky latitudes “productive” and war in the rest of the world “unproductive” may be the extreme case. The labels smack of a moral judgment, that the lucky latitudes' wars have been good while everyone else's have been bad, even though there are plenty of perspectives from
which that is patent nonsense. In terms of sheer numbers killed, for instance, productive war has vastly outstripped the unproductive version. Some of history's most productive wars—in the sense I use that expression, of accelerating Leviathan's growth—have been among its most dastardly. Whatever else we might say about the Yanomami, they never crucified their enemies, as the Romans regularly did.