THE DEMOGR APHIC CONSEQUENCES - Dark Age America: Climate Change, Cultural Collapse, and the Hard Future Ahead - John Michael Greer

Dark Age America: Climate Change, Cultural Collapse, and the Hard Future Ahead - John Michael Greer (2016)

Chapter 3. THE DEMOGR APHIC CONSEQUENCES

THE THREE ENVIRONMENTAL SHIFTS DISCUSSED IN THE PREvious chapter—the ecological impacts of a sharply warmer and dryer climate, the flooding of coastal regions due to rising sea levels, and the long-term consequences of industrial America’s frankly brainless dumping of persistent radiological and chemical poisons—all involve changes to the North American continent that will endure straight through the deindustrial dark age ahead and will help shape the history of the successor cultures that will rise amid our ruins. For millennia to come, the peoples of North America will have to contend with drastically expanded deserts, coastlines many miles further inland than they are today, and the presence of dead zones where nuclear or chemical wastes in the soil and water make human settlement impossible.

Agriculture can adapt to a wide range of climate shifts, and some highly promising moves toward adapting agricultural methods to the changed climate of the deindustrial era are already under way.1 That said, there is a fairly limited set of regions in which field agriculture of something like the familiar sort will be viable in a post-fossil fuel age. Those regions cluster in the Eastern Seaboard from the new coast west to the Alleghenies and the Great Lakes and in river valleys in the eastern half of the Mississippi basin.

The Midwestern grasslands will support pastoral grazing, and the jungle belts around the new Gulf Coast will be suitable for tropical horticulture once the soil has a chance to recover. The vast inland deserts will support a few people, much the way the inland regions of the Sahara Desert do today, and a narrow strip of land along the Pacific coast will be habitable to roughly the same degree that the northern shores of Africa are at present. Meanwhile, all through these regions, the fertile and the barren alike, there will be dead zones contaminated by nuclear or chemical poisons, where no one can live.

As a result, deindustrial North America will support many fewer people than it did in 1880 or so, before new agricultural technologies dependent on fossil fuels launched the population boom that is peaking in our time. This also implies, of course, that deindustrial North America will support many, many fewer people than it does today. For obvious reasons, it’s worth talking about the processes by which today’s seriously overpopulated North America will become the sparsely populated continent of the coming dark age—but that discussion is going to require a confrontation with a certain kind of petrified irrelevancy all too common in our time.

There are two officially sanctioned scripts into which discussions of overpopulation are inevitably shoehorned in today’s industrial world. Like most cultural phenomena in today’s industrial world, the scripts just mentioned hew closely to the faux-liberal and faux-conservative narratives that dominate so much of contemporary thought.2 The scripts differ along the usual lines: that is to say, the faux-liberal script is well-meaning and ineffectual, while the faux-conservative script is practicable and evil.

Thus the faux-liberal script insists that overpopulation is a terrible problem, we ought to do something about it, and the things we should do about it are all things that don’t work, won’t work, and have been being tried over and over again for decades without having the slightest effect on the situation. The faux-conservative script insists that overpopulation is a terrible problem but only because it’s people of, ahem, the wrong skin color who are overpopulating, ahem, our country: that is, overpopulation means immigration, and immigration means let’s throw buckets of gasoline onto the flames of ethnic conflict, so it can play its standard role in ripping apart a dying civilization with even more verve than it otherwise would.

Overpopulation and immigration policy are not the same thing. Neither are depopulation and the mass migrations of whole peoples for which German historians of the post-Roman dark ages coined the neat term völkerwanderung, “the wandering of nations,” which are the corresponding phenomena in eras of decline and fall. For that reason, the faux-conservative side of the debate, along with the usually unmentioned realities of immigration policy in today’s America and the far greater and more troubling realities of mass migration and ethnogenesis that will follow in due time, will be covered a little later in this chapter. For now I want to talk about overpopulation as such, and therefore about the faux-liberal side of the debate and the stark realities of depopulation that are waiting in the future.

All this needs to be put in its proper context. In 1962, the year I was born, there were about three and a half billion human beings on this planet. Today, there are more than seven billion of us. That staggering increase in human numbers has played an immense and disastrous role in backing today’s industrial world into the corner where it now finds itself. Among all the forces driving us toward an ugly future, the raw pressure of human overpopulation, with the huge and rising resource requirements it entails, is among the most important.

That much is clear. What to do about it is something else again. You’ll still hear people insisting that campaigns to convince people to limit their reproduction voluntarily ought to do the trick, but such campaigns have been ongoing since many decades before I was born, and human numbers more than doubled anyway. If a strategy has failed every time it’s been tried, insisting that we ought to do it again isn’t a useful suggestion. That applies not only to the campaigns just noted, but to all the other proposals to slow or stop population growth that have been tried repeatedly and failed just as repeatedly over the decades just past.

These days, a great deal of the hopeful talk around the subject of limits to overpopulation has refocused on what’s called the demographic transition: the process, visible in the population history of most of today’s industrial nations, whereby people start voluntarily reducing their reproduction when their income and access to resources rise above a certain level. It’s a real effect, though its causes are far from clear. The problem here is simply that the resource base that would make it possible for enough of the world’s population to have the income and access to resources necessary to trigger a worldwide demographic transition simply don’t exist.

As fossil fuels and a galaxy of other nonrenewable resources slide down the slope of depletion at varying rates, for that matter, it’s becoming increasingly hard for people in the industrial nations to maintain their familiar standards of living. It may be worth noting that this hasn’t caused a sudden upward spike in population growth in those countries where downward mobility has become most visible. The demographic transition, in other words, doesn’t work in reverse, and this points to a crucial fact that hasn’t necessarily been given the weight it deserves in conversations about overpopulation.

The vast surge in human numbers that dominates the demographic history of modern times is wholly a phenomenon of the industrial age. Other historical periods have seen modest population increases but nothing on the same scale, and those have reversed themselves promptly when ecological limits came into play. Whatever the specific factors and forces that drove the population boom, then, it’s a pretty safe bet that the underlying cause was the one factor present in industrial civilization that hasn’t played a significant role in any other human society: the exploitation of vast quantities of extrasomatic energy—that is, energy that doesn’t come from human or animal muscle. Place the curve of increasing energy per capita worldwide next to the curve of human population worldwide, and the two move very nearly in lockstep: thus it’s fair to say that human beings, like yeast, respond to increased access to energy with increased reproduction.

Does that mean that we’re going to have to deal with soaring population worldwide for the foreseeable future? No, and hard planetary limits to resource extraction are the reasons why. Without the huge energy subsidy to agriculture contributed by fossil fuels, producing enough food to support seven billion people won’t be possible. We saw a preview of the consequences in 2008 and 2009, when the spike in petroleum prices caused a corresponding spike in food prices and a great many people around the world found themselves scrambling to get enough to eat on any terms at all. The riots and revolutions that followed grabbed the headlines, but another shift that happened around the same time deserves more attention: birth rates in many Third World countries decreased noticeably and have continued to trend downward since then.3

The same phenomenon can be seen elsewhere. Since the collapse of the Soviet Union, most of the former Soviet republics have seen steep declines in rates of live birth, life expectancy, and most other measures of public health, while death rates have climbed well above birth rates and stayed there.4 For that matter, since the financial crisis of 2008, birth rates in the United States have dropped sharply; these days, immigration is the only reason the population of the United States doesn’t register significant declines year after year.

This is the wave of the future. As fossil fuel and other resources dwindle, and economies dependent on those resources become less and less able to provide people with the necessities of life, the population boom will turn into a population bust. The base scenario in 1972’s The Limits to Growth, still the most accurate (and thus inevitably the most vilified) model of the future into which we’re stumbling blindly just now, put the peak of global population somewhere around 2030: that is, fourteen years from now. Recent declines in birth rates in areas that were once hotbeds of population growth, such as Latin America and the Middle East, can be seen as the leveling off that always occurs in a population curve before decline sets in.

That decline is likely to go very far indeed. That’s partly a matter of straightforward logic: because global population has been artificially inflated by pouring extrasomatic energy into boosting the food supply and providing other necessary resources to human beings, the exhaustion of economically extractable reserves of the fossil fuels that made that process possible will knock the props out from under global population figures. Still, historical parallels also have quite a bit to offer here: extreme depopulation is a common feature of the decline and fall of civilizations, with up to ninety-five percent population loss over the one to three centuries that the fall of a civilization usually takes.

Suggest that to people nowadays and, once you get past the usual reactions of denial and disbelief, the standard assumption is that population declines so severe could happen only if there were catastrophes on a truly gargantuan scale. That’s an easy assumption to make, but it doesn’t happen to be true. Just as it didn’t take vast public orgies of copulation and childbirth to double the planet’s population over the last half-century, it wouldn’t take equivalent exercises in mass death to halve the planet’s population over the same time frame. The ordinary processes of demographic change can do the trick all by themselves.

Let’s explore that by way of a thought experiment. Between family, friends, coworkers, and the others that you meet in the course of your daily activities, you probably know something close to a hundred people. Every so often, in the ordinary course of events, one of them dies—depending on the age and social status of the people you know, that might happen once a year, once every two years, or what have you. Take a moment to recall the most recent death in your social circle, and the one before that, to help put the rest of the thought experiment in context.

Now imagine that from this day onward, among the hundred people you know, one additional person—one person more than you would otherwise expect to die—dies every year, while the rate of birth remains the same as it is now. Imagine that modest increase in the death rate affecting the people you know. One year, an elderly relative of yours doesn’t wake up one morning; the next, a barista at the place where you get coffee on the way to work dies of cancer; the year after that, a coworker’s child comes down with an infection the doctors can’t treat, and so on. A noticeable shift? Granted, but it’s not Armageddon; you attend a few more funerals than you’re used to, make friends with the new barista, and go about your life until one of those additional deaths is yours.

Now take that process and extrapolate it out. (Those of my readers who have the necessary math skills should take the time to crunch the numbers themselves.) Over the course of three centuries, an increase in the crude death rate of one percent per annum, given an unchanged birth rate, is sufficient to reduce a population to five percent of its original level. Vast catastrophes need not apply; of the traditional four horsemen, War, Famine, and Pestilence can sit around drinking beer and playing poker. The fourth horseman, in the shape of a modest change in crude death rates, can do the job all by himself.

Now imagine the same scenario, except that there are three additional deaths each year in your social circle, rather than one. That would be considerably more noticeable, but it still doesn’t look like the end of the world—at least until you do the math. An increase in the crude death rate of three percent per annum, given an unchanged birth rate, is enough to reduce a population to five percent of its original level within a single century. In global terms, if world population peaks around eight billion in 2030, a decline on that scale would leave four hundred million people on the planet by 2130.

In the real world, of course, things are not as simple or smooth as they are in the thought experiment just offered. Birth rates are subject to complex pressures and vary up and down depending on the specific pressures a population faces, and even small increases in infant and child mortality have a disproportionate effect by removing potential breeding pairs from the population before they can reproduce. Meanwhile, population declines are rarely anything like so even as the thought experiment suggests. Those other three horsemen, in particular, tend to get bored of their poker game at intervals and go riding out to give the guy with the scythe some help with the harvest. War, famine, and pestilence are common events in the decline and fall of a civilization, and the twilight of the industrial world is likely to get its fair share of them.

Thus it probably won’t be a matter of one or two or three more deaths a year, every year. Instead, one year, war breaks out, most of the young men in town get drafted, and half of them come back in body bags. Another year, after a string of bad harvests and food shortages, the flu comes through, and a lot of people who would have shaken it off under better conditions are just that little bit too malnourished to survive. Yet another year, a virus shaken out of its tropical home by climate change and ecosystem disruption goes through town, and fifteen percent of the population dies in eight ghastly months. That’s the way population declines happen in history.

In the twilight years of the Roman world, to cite an example we’ll be using repeatedly in the chapters ahead, a steady demographic contraction was overlaid by civil wars, barbarian invasions, economic crises, famines, and epidemics.5 The total population decline varied significantly from one region to another, but even the relatively stable parts of the Eastern Empire seem to have had around a fifty percent loss of population, while some areas of the Western Empire suffered far more drastic losses—Britain in particular was transformed from a rich, populous, and largely urbanized province to a land of silent urban ruins and small, scattered villages of subsistence farmers where even so simple a technology as wheel-thrown pottery became a lost art.

The classic lowland Maya are another good example along the same lines. Hammered by climate change and topsoil loss, the Maya heartland went through a rolling collapse a century and a half in length that ended with population levels maybe five percent of what they’d been at the start of the Terminal Classic period, and most of the great Maya cities became empty ruins rapidly covered by the encroaching jungle.6 Those of my readers who have seen pictures of tropical foliage burying the pyramids of Tikal and Copan may find it helpful to imagine scenes of the same kind in the ruins of Atlanta and Austin a few centuries from now. That’s the kind of thing that happens when an urbanized society suffers severe population loss during the decline and fall of a civilization.

That, in turn, is what has to be factored into any realistic forecast of dark age America: there will be many, many fewer people inhabiting North America a few centuries from now than there are today. Between the depletion of the fossil fuel resources necessary to maintain today’s hugely inflated numbers and the degradation of North America’s human carrying capacity by climate change, sea level rise, and persistent radiological and chemical pollution, the continent simply won’t be able to support all that many people. The current total is about 470 million—35 million in Canada, 314 million in the US, and 121 million in Mexico, according to the latest figures I was able to find—and something close to five percent of that—say, 20 to 25 million—might be a reasonable midrange estimate for the human population of the North American continent when the population implosion finally bottoms out a few centuries from now.

Now, of course, those 20 to 25 million people won’t be scattered evenly across the continent. There will be very large regions—for example, the nearly lifeless, sun-blasted wastelands that climate change will make of the southern Great Plains, the Great Basin, and the Sonoran Desert—where human settlement will be as sparse as it is today in the bleakest parts of the Sahara Desert. There will be other areas—for example, the Great Lakes region and the Gulf Coast from Mexico around to the shallow seas where Florida used to be—where population will be relatively dense by Dark Age standards, and towns of modest size may even thrive if they happen to be in defensible locations.

The nomadic herding folk of the Midwestern prairies, and the other human ecologies that will spring up in the varying ecosystems of deindustrial North America, will all gradually settle into a more or less stable population level, at which births and deaths balance each other and the consumption of resources stays at or below sustainable levels of production. That’s what happens in human societies that don’t have the dubious advantage of a torrent of non-renewable energy reserves to distract them temporarily from the hard necessities of survival.

It’s getting to that level that’s going to be a bear. The mechanisms of population contraction are simple enough, and as suggested above, they can have a dramatic impact on historical time scales without cataclysmic impact on the scale of individual lives. The same principle applies to the second half of the demography of dark age America: the role of mass migration and ethnogenesis in the birth of the cultures that will emerge on this continent when industrial civilization is a fading memory.

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It’s one thing to suggest that North America a few centuries from now might have something like five percent of its current population. It’s quite another thing to talk about exactly whose descendants will comprise that five percent—and yes, I know that raising that issue is normally a very good way to spark a shouting match in which who-did-what-to-whom rhetoric plays its usual role in drowning out everything else.

Now, of course, there’s a point to talking about, and learning from, the abuses inflicted by groups of people on other groups of people over the last five centuries or so of North American history. Such discussions, though, have very little to offer the theme of this book, because history may be a source of moral lessons, but it’s not a moral phenomenon. A glance back over our past shows clearly enough that who won, who lost, who ended up ruling a society, and who ended up enslaved or exterminated by that same society, was not determined by moral virtue or by the justice of one or another cause but by the crassly pragmatic factors of military, political, and economic power. No doubt most of us would rather live in a world that didn’t work that way, but here we are, and morality remains a matter of individual choices—yours and mine—in the face of a cosmos that’s sublimely unconcerned with our moral beliefs.

Thus we can take it for granted that just as the borders that currently divide North America were put there by force or the threat of force, the dissolution of those borders and their replacement with new lines of division will happen the same way. For that matter, it’s a safe bet that the social divisions, ethnic and otherwise, of the successor cultures that emerge in the aftermath of our downfall will be established and enforced by means no more just or fair than the ones that distribute wealth and privilege to the different social and ethnic strata in today’s North American nations. Again, it would be pleasant to live in a world where that isn’t true, but we don’t.

I apologize to any of my readers who are offended or upset by these points. In order to make any kind of sense of the way that civilizations fall—and more to the point, the way that ours is falling—it’s essential to get past the belief that history is under any obligation to hand out rewards for good behavior and punishments for the opposite, or for that matter, the other way around. Over the years and decades and centuries ahead of us, as industrial civilization crumbles, a great many people who believe with all their hearts that their cause is right and just are going to die anyway, and there will be no shortage of brutal, hateful, vile individuals who claw their way to the top—for a while, at least. One of the reliable features of dark ages is that while they last, the top of the heap is a very unsafe place to be.

North America being what it is today, a great many people considering the sort of future I’ve just sketched out start thinking about the potential for ethnic conflict, especially but not only in the United States. It’s an issue worth discussing, and not only for the obvious reasons. Conflict between ethnic groups is quite often a major issue in the twilight years of a civilization, for reasons we’ll discuss shortly, but it’s also self-terminating, for an interesting reason: traditional ethnic divisions don’t survive dark ages. In an age of political dissolution, economic implosion, social chaos, demographic collapse, and mass migration, the factors that maintain ethnic divisions in place don’t last long. In their place, new ethnicities emerge. It’s a commonplace of history that dark ages are the cauldron from which nations are born.

So we have three stages, which overlap to a greater or lesser degree: a stage of ethnic conflict, a stage of ethnic dissolution, and a stage of ethnogenesis. Let’s take them one at a time.

The stage of ethnic conflict is one effect of the economic contraction that’s inseparable from the decline of a civilization. If a rising tide lifts all boats, as economists of the trickle-down school used to insist, a falling tide has a much more differentiated effect, since each group in a declining society does its best to see to it that as much as possible of the costs of decline land on someone else.7 Since each group’s access to wealth and privilege determines fairly exactly how much influence it has on the process, it’s one of the constants of decline and fall that the costs and burdens of decline trickle down, landing with most force on those at the bottom of the pyramid.

That heats up animosities across the board: between ethnic groups, between regions, between political and religious divisions, you name it. Since everyone below the uppermost levels of wealth and power loses some of what they’ve come to expect, and since it’s human nature to pay more attention to what you’ve lost than to the difference between what you’ve retained and what someone worse off than you has to make do with, everyone’s aggrieved, and everyone sees any attempt by someone else to better their condition as a threat. That’s by no means entirely inaccurate—if the pie’s shrinking, any attempt to get a wider slice has to come at somebody else’s expense—but it fans the flames of conflict even further, helping to drive the situation toward the inevitable explosions.

One very common and very interesting feature of this process is that the increase in ethnic tensions tends to parallel a process of ethnic consolidation. In the United States a century ago, for example, the division of society by ethnicity wasn’t anything so like as simple as it is today. The uppermost caste in most of the country wasn’t simply white, it was white male Episcopalians whose ancestors got here from northwestern Europe before the Revolutionary War. Irish ranked below Germans but above Italians, who looked down on Jews, and so on down the ladder to the very bottom, which was occupied by either African Americans or Native Americans depending on locality. Within any given ethnicity, furthermore, steep social divisions existed, microcosms of a hierarchically ordered macrocosm. Gender distinctions and a great many other lines of fracture combined with the ethnic divisions just noted to make American society in 1916 as intricately caste-ridden as any culture on the planet.

The partial dissolution of many of these divisions has resulted inevitably in the hardening of those that remain. That’s a common pattern, too: consider the way that the rights of Roman citizenship expanded step by step from the inhabitants of the city of Rome itself to larger and larger fractions of the people it dominated, until finally every free adult male in the Empire was a Roman citizen by definition. Parallel to that process came a hardening of the major divisions, between free persons and slaves on the one hand, between citizens of the Empire and the barbarians outside its borders, and between adherents of the major religious blocs into which the tolerant paganism of Rome’s heyday was divided. The result was the same in that case as it is in ours: traditional, parochial jealousies and prejudices focused on people one step higher or lower on the ladder of caste give way to new loyalties and hatreds, uniting ever-greater fractions of the population into increasingly large and explosive masses.

The way that this interlocks with the standard mechanisms of decline and fall will be a central theme throughout this book. The crucial detail, though, is that a society riven by increasingly bitter divisions of the sort just sketched out is very poorly positioned to deal with external pressure or serious crisis. “Divide and conquer,” the Romans liked to say during the centuries of their power: splitting up their enemies and crushing them one at a time was the fundamental strategy they used to build their empire. On the way down, though, it was the body of Roman society that did the dividing, tearing itself apart along every available line of schism, and Rome was accordingly conquered in its turn. That’s usual for falling civilizations, and we’re well along the same route in the United States today.

Ethnic divisions thus routinely play a significant role in the crash of civilizations. Still, as noted above, the resulting chaos quickly shreds the institutional arrangements that make ethnic divisions endure in a settled society. Charismatic leaders emerge out of the chaos, and those who are capable of envisioning and forming alliances across ethnic lines succeed where their rivals fail; the reliable result is a chaotic melting pot of armed bands and temporary communities drawn from all available sources. When the Huns first came west from the Eurasian steppes around 370 CE, for example, they were apparently a federation of related Central Asian tribes; by the time of Attila, rather less than a century later, his vast armies included warriors from most of the ethnic groups of Eastern Europe.8 We don’t even know what their leader’s actual name was. “Attila” was a nickname—“Daddy”—in Visigothic, the lingua franca among the eastern barbarians at that time.

The same chaotic reshuffling was just as common on the other side of the collapsing Roman frontiers. The province of Britannia, for instance, had long been divided into ethnic groups with their own distinct religious and cultural traditions. In the wake of the Roman collapse and the Saxon invasions, the survivors who took refuge in the mountains of the West forgot the old divisions, and took to calling themselves by a new name: Combrogi, “fellow-countrymen” in old Brythonic.9 Nowadays that’s Cymry, the name the Welsh use for themselves. Not everyone who ended up as Combrogi was British by ancestry—one of the famous Welsh chieftains in the wars against the Saxons was a Visigoth named Theodoric.10 Nor were all the people on the other side Saxons—one of the leaders of the invaders was a Briton named Caradoc ap Cunorix, the “Cerdic son of Cynric” of the Anglo-Saxon Chronicle.11

It’s almost impossible to overstate the efficiency of the blender into which every political, economic, social, and ethnic manifestation got tossed in the last years of Rome. My favorite example of the raw confusion of that time is the remarkable career of another Saxon leader named Odoacer. He was the son of one of Attila the Hun’s generals, but he got involved in Saxon raids on Britain after Attila’s death. Sometime in the 460s, when the struggle between the Britons and the Saxons was more or less stuck in deadlock, Odoacer decided to look for better pickings elsewhere and led a Saxon fleet that landed at the mouth of the Loire in western France.12 For the next decade or so, more or less in alliance with Childeric, king of the Franks, he fought the Romans, the Goths, and the Bretons there.

When the Saxon hold on the Loire was finally broken, Odoacer took the remains of his force and joined Childeric in an assault on Italy. No records survive of the fate of that expedition, but it apparently didn’t go well. Odoacer next turned up, without an army, in what’s now Austria and was then the province of Noricum. It took him only a short time to scrape together a following from the random mix of barbarian warriors to be found there, and in 476 he marched on Italy again and overthrew the equally random mix of barbarians who had recently seized control of the peninsula.

The Emperor of the West just then, the heir of the Caesars and titular lord of half the world, was a boy named Romulus Augustulus. In a fine bit of irony, he also happened to be the son of Attila the Hun’s Greek secretary, a sometime ally of Odoacer’s father. This may be why, instead of doing the usual thing and having the boy killed, Odoacer basically told the last Emperor of Rome to run along and play. That sort of clemency was unusual, and it wasn’t repeated by the next barbarian warlord in line; fourteen years later Odoacer was murdered by order of Theodoric, king of the Ostrogoths, who proceeded to take his place as temporary master of the corpse of imperial Rome.

Soldiers of fortune, or of misfortune, weren’t the only people engaged in this sort of heavily armed tour of the post-Roman world during those same years. Entire nations were doing the same thing. Those of my readers who have been watching North America’s climate come unhinged may be interested to know that severe droughts in Central Asia may have been the trigger that kick-started the process, pushing nomadic tribes out of their traditional steppe territories in a desperate quest for survival. Whether or not that’s what pushed the Huns into motion, the westward migration of the Huns forced other barbarian peoples further west to flee for their lives, and the chain of dominoes thus set in motion played a massive role in creating the chaos in which figures like Odoacer rose and fell. It’s a measure of the sheer scale of these migrations that, before Rome started to topple, many of the ancestors of today’s Spaniards lived in what’s now the Ukraine.

And afterward? The migrations slowed and finally stopped; the warlords became kings; and the people who found themselves in some more or less stable kingdom began the slow process by which a random assortment of refugees, barbarian invaders, and military veterans from the far corners of the Roman world became the first draft of a nation. The former province of Britannia, for example, became seven Saxon kingdoms and a varying number of Celtic ones; and then began the slow process of war and coalescence out of which England, Scotland, Wales, and Cornwall gradually emerged. Elsewhere, the same process moved at varying rates; new nations, languages, ethnic groups came into being. The cauldron of nations had come off the boil, and the history of Europe settled down to a somewhat less frenetic rhythm.

I’ve used post-Roman Europe as a convenient and solidly documented example, but transformations of the same kind are commonplace whenever a civilization goes down. The smaller and more isolated the geographical area of the civilization that falls, the less likely mass migrations are—ancient China, Mesopotamia, and central Mexico had plenty of them, while the collapse of the classic Maya and Heian Japan featured a shortage of wandering hordes—but the rest of the story is among the standard features you get with societal collapse. North America is neither small nor isolated, and so it’s a safe bet that we’ll get a tolerably complete version of the usual process right here in the centuries ahead.

What does that mean in practice? It means, to begin with, that a rising spiral of conflict along ethnic, cultural, religious, political, regional, and social lines will play an ever-larger role in North American life for decades to come. Those of my readers who have been paying attention to events, especially but not only in the United States, will have already seen that spiral getting under way. As the first few rounds of economic contraction have begun to bite, the standard response of every group you care to name has been to try to get the bite taken out of someone else. Listen to the insults being flung around in the political controversies of the present day—the thieving rich, the shiftless poor, and the rest of it—and notice how many of them amount to claims that wealth that ought to belong to one group of people is being unfairly held by another. In those claims, you can hear the first whispers of the battle cries that will be shouted as the usual internecine wars begin to tear our civilization apart.

As those get under way, for reasons we’ll discuss at length later on, governments and the other institutions of civil society will come apart at the seams, and the charismatic leaders already mentioned will rise to fill their place. In response, existing loyalties will begin to dissolve as the normal process of warband formation kicks into overdrive. In such times a strong and gifted leader like Attila the Hun can unite any number of contending factions into a single overwhelming force, but at this stage such things have no permanence; once the warlord dies, ages, or runs out of luck, the forces so briefly united will turn on each other and plunge the continent back into chaos.

There will also be mass migrations, and far more likely than not, these will be on a scale that would have impressed Attila himself. That’s one of the ways that the climate change our civilization has unleashed on the planet is a gift that just keeps on giving; until the climate settles back down to some semblance of stability and sea levels have risen as far as they’re going to rise, people in vulnerable areas are going to be forced out of their homes by one form of unnatural catastrophe or another, and the same desperate quest for survival that may have sent the Huns crashing into Eastern Europe will send new hordes of refugees streaming across the landscape. Some of those hordes will have starting points within the United States—I expect mass migrations from Florida as the seas rise, and from the Southwest as drought finishes tightening its fingers around the Sun Belt’s throat—while others will come from further afield.

Five centuries from now, as a result, it’s entirely possible that most people in the upper Mississippi valley will be of Brazilian ancestry, and that the inhabitants of the Hudson’s Bay region sing songs about their long-lost homes in drowned Florida, while languages descended from English may be spoken only in a region extending from New England to the isles of deglaciated Greenland. Nor will these people necessarily think of themselves in any of the national and ethnic terms that come so readily to our minds today. It’s by no means impossible that somebody may claim to be the President of the United States (though it may be pronounced Presden of Meriga by that time), or what have you, just as Charlemagne and his successors claimed to be the emperors of Rome. Just as the Holy Roman Empire was proverbially neither holy, nor Roman, nor an empire, neither the office nor the nation at that future time is likely to have much of anything to do with its nominal equivalent today—and there will certainly be nations and ethnic groups in that time that have no parallel today.

One implication of these points may be worth noting here, as we move deeper into the stage of ethnic conflict. No matter what your ethnic group, dear reader, no matter how privileged or underprivileged it may happen to be in today’s world, it will almost certainly no longer exist as such when industrial civilization on this continent descends into the deindustrial dark age ahead. Such of your genes as make it through centuries of die-off and ruthless Darwinian selection will be mixed with genes from many other nationalities and corners of the world, and it’s probably a safe bet that the people who carry those genes won’t call themselves by whatever label you call yourself. When a civilization falls the way ours is falling, that’s how things generally go.