Special Report

The World Will Be More Crowded -- With Old People

Actually, the children aren't our future.

Demography is not destiny, as is sometimes claimed. The human race could be wiped out by a plague or an asteroid, or transformed by some new technology. But no matter what, today's patterns of fertility, migration, and mortality fundamentally determine how much society will or can change for many generations to come.

And what demography tells us is this: The human population will continue to grow, though in a very different way from in the past. The United Nations' most recent "mid-range" projection calls for an increase to 8 billion people by 2025 and to 10.1 billion by century's end.

Until quite recently, such population growth always came primarily from increases in the numbers of young people. Between 1950 and 1990, for example, increases in the number of people under 30 accounted for more than half of the growth of the world's population, while only 12 percent came from increases in the ranks of those over 60.

But in the future it will be the exact opposite. The U.N. now projects that over the next 40 years, more than half (58 percent) of the world's population growth will come from increases in the number of people over 60, while only 6 percent will come from people under 30. Indeed, the U.N. projects that by 2025, the population of children under 5, already in steep decline in most developed countries, will be falling globally -- and that's even after assuming a substantial rebound in birth rates in the developing world. A gray tsunami will be sweeping the planet.

Which countries will be aging most rapidly in 2025? They won't be in Europe, where birth rates fell comparatively gradually and now show some signs of ticking up. Instead, they'll be places like Iran and Mexico, which experienced youth bulges that were followed quickly by a collapse in birth rates. In just 35 years, both Iran and Mexico will have a larger percentage of their populations over 60 than France does today. Other places with birth rates now below replacement levels include not just old Europe but also developing countries such as Brazil, Chile, China, Lebanon, Tunisia, South Korea, and Vietnam.

Because of the phenomenon of hyper-aging in the developing world, another great variable is already changing as well: migration. In Mexico, for example, the population of children age 4 and under was 434,000 less in 2010 than it was in 1996. The result? The demographic momentum that fueled huge flows of Mexican migration to the United States has waned, and will wane much more in the future. Already, the net flow of illegal Mexican immigration northward has slowed to a trickle. With fewer children to support and not yet burdened by a huge surge of elders, the Mexican economy is doing much better than in the past, giving people less reason to leave. By 2025, young people on both sides of the border may struggle to understand why their parents' generation built this huge fence.

Despite these trends, most people conclude from their day-to-day lives that overpopulation is a serious problem. One reason is that more than half the world's population is crowded into urban areas. The high cost of raising children in mega-cities is a prime reason that global birth rates continue to fall, yet urbanization also makes the larger trend toward depopulation difficult for most to grasp. If the downward trend in birth rates doesn't moderate and stabilize as the U.N. assumes it will, the world as a whole could be losing population as soon as midcentury. And yet few people will likely see that turning point coming, so long as humans continue to pack into urban areas and increase their consumption of just about everything.

Another related megatrend is the rapid change in the size, structure, and nature of the family. In many countries, such as Germany, Japan, Russia, and South Korea, the one-child family is now becoming the norm. This trend creates a society in which not only do most people have no siblings, but also no aunts, uncles, cousins, nieces, or nephews. Many will lack children of their own as well. Today about one in five people in advanced Western countries, including the United States, remains childless. Huge portions of the world's population will thus have no biological relatives except their parents.

And even where children continue to be born, they are being raised under radically different circumstances, as country after country has seen divorce and out-of-wedlock births surge and the percentage of children living with both of their married parents drop sharply. So not only is the quantity of children in the world poised to shrink rapidly, but on current trends, a near majority of them will be raised in ways that are today strongly associated with negative life outcomes.

Are there signs of any of these trends reversing before 2025? Only a few. The percentage of the world's population raised in religious households is bound to rise, if only because adherents to fundamentalism, whether Christians, Jews, or Muslims, tend to have substantially more children than their secular counterparts. And there are certainly many ways -- from increased automation and delayed retirement to health-care reform to the provision of baby bonuses -- for societies to at least partially adjust to the tidal shift in global demographics.

But don't count on it. To make such sweeping changes would require a widespread understanding of the century's great paradox: The planet may be bursting, but most of this new population is made up of people who have already been born. So get ready for a planet that's a whole lot more crowded -- with old people.

Illustration by Oliver Munday for FP

Special Report

Problems Will Be Global -- And Solutions Will Be, Too

A more multilateral world is just the beginning.

Before considering the world in 2025, 14 years from now, it is worth remembering the world 14 years ago, in 1997. Back then, the United States was the sole superpower, its immensity and dominance of the international system so evident as to trigger the resentful label of "hyperpower" from the French foreign minister. The American economy was expanding fast enough to leave the country a healthy and growing surplus by the end of Bill Clinton's presidency three years later. The European Union, then still only four years old, had just 15 members; the euro did not exist. The wars dominating the headlines were in Europe: Bosnia, Croatia, and, soon, Kosovo. The term BRICs -- the Goldman Sachs label attached to the fast-growing emerging markets of Brazil, Russia, India, and China -- had not yet been invented. The Internet was booming, but social media did not exist.

You get the point: A lot can change in 14 years, and rarely in ways foreseen. In the spirit of proper humility, then, here's my take on what the landscape of global diplomacy will look like a decade and a half from now:

For starters, the world will be much more multilateral. By 2025 the U.N. Security Council will have expanded from the present 15 members to between 25 and 30 and will include, either as de jure or de facto permanent members, Brazil, India, Japan, South Africa, either Egypt or Nigeria, and either Indonesia or Turkey. At the same time, regional organizations on every continent -- the African Union, the Association of Southeast Asian Nations, some version of the Organization of American States -- will be much stronger. Each will follow its own version of economic and political integration, inspired by the European Union, and many will include representation from smaller subregional organizations. In the Middle East, Israel, Palestine, Jordan, Syria, and Turkey could provide the core of a new Middle East free trade area; alternatively the European Union could be interlocked with an emerging Mediterranean Union.

Driving this massive multilateralization is the increasingly global and regional nature of our problems, combined with an expanding number of countries splitting off from existing states. National governments will remain essential for many purposes, but managing bilateral relations and engaging in successful global negotiations with nearly 200 states will become increasingly unwieldy. So we'll negotiate territorial disputes in the South China Sea in a regional framework and deal with crises in Ivory Coast or Guinea through the African Union or even smaller subregional forums. At the global level, the speed and flexibility necessary to resolve crises require smaller groups like the G-20, while long-term legitimacy and durability still require the representation of all countries affected by a particular issue through large standing organizations.

As for individual countries, the states that will be the strongest in 2025 will be those that have figured out how to do more with less. They will be those governments that have successfully embraced radical sustainability -- maintaining vibrant economies through largely renewable energy and creative reuse of just about everything. The leader will be Japan, a great civilization that has for centuries pioneered spectacularly beautiful ways of appreciating and coexisting with nature. As China's youth seek more of everything, Japan's are prepared to embrace a far more sustainable path. Scandinavia, Germany, New Zealand, and possibly South Korea will also be strong; many emerging or even less developed economies have real potential, if they can tap into their indigenous habits of conservation. Embracing sustainable growth will challenge the United States; its national renewal will depend on connecting its traditions of innovation, decentralization, and liberty with a narrative of protecting America's natural bounty. Think America the Beautiful more than the Star-Spangled Banner.

But the most dramatic changes between 2011 and 2025 won't take place at the level of statecraft and grand strategy; they are likely to happen as new technologies continue to transform businesses, civic organizations of all kinds, universities, foundations, and churches -- now able to self-organize as never before around issues they care about. The American social revolution that Alexis de Tocqueville observed in the early 19th century, of citizens joining groups of every conceivable kind, is about to go global, forever changing the relationship between citizens and their governments, and governments with each other. The Arab revolutions are but the first taste of this larger change.

These predictions may appear rosy. In fact, the enormous changes on the horizon will require major crises, even cataclysm, before they can materialize. It took World War I to generate the political will and circumstances necessary to create the League of Nations; it took World War II to create the United Nations; it took the worst economic crisis since the 1930s to force the expansion of the G-8 into the G-20. Just imagine what it will take to break the decades-old logjam of Security Council reform. And creating and changing multilateral organizations is child's play next to the profound changes in public and private behavior required to move away from the more-is-better economic model to one which accepts that our resources are finite on a planetary scale.

Yet the sources of potential crises and disasters of a magnitude sufficient to force systemic change are all around us: Climate change is driving countries closer to the extremes of desert and jungle, droughts and floods, while a global pandemic or a nuclear terrorist attack would have a similar impact. This is not Malthusian gloom, however. As Robert Wright argues in Nonzero: The Logic of Human Destiny, catastrophe is terrible for individual human beings but beneficial for humanity as a whole. As the full consequences of genuinely global interconnectedness continue to make themselves felt, the world of both states and the societies they represent will have no choice but to adapt.

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