Breeding like Rabbits

I was actually just finishing my review of Pat Buchanan's The Death of the West when I saw the story from Reuters. (Links are to the left; I prefer not to imbed them.) As you know, The Death of the West argues that the very existence of Western countries is in peril because their fertility rates are below those needed to maintain their populations. Now the Centers for Disease Control & Prevention say that is no longer true with regard to the United States. This development is actually just a return to replacement levels, but you may have already seen the expression "new babyboom" in a few places. Probably you will see quite a lot of it by mid-summer.

Demographic history is not one of my chief interests, but I do know enough about it to realize that it is one of those "everything you know is a lie" subjects. For instance, those nice, smooth, population-growth curves that you see in books by people like Paul Ehrlich are wildly misleading. The population of France, for instance, expanded into the fourteenth century, crashed with the plague, and then oscillated between 12 million and 20 million before beginning a steady rise in the late 17th century. Pretty much the same thing happened in China at pretty much the same time.

The world's population jumps from plateau to plateau and then takes a rest. The world's major population centers have always been more or less in sync. It is sometimes said that you have to go back to Roman times to find anything like today's low growth rates for Western Europe. True enough: the phenomenon started in the late Republic, though it never applied to the east under the Empire. In any case, much the same seems to have been true of Han China; Turkic peoples overran the depopulated north of China at about the time the Germans were overrunning the late Roman Empire.

We are still in sync, on the scale of a hundred years or so. In the unlikely event that present trends continue, the population of China will increase from 1.3 billion now to 1.5 billion in 2050, and then stabilize or decline. There are places in the world with explosive fertility rates, notably the Middle East and Africa; low child-mortality is still new there. Even moderately developed countries tend to fall to replacement level. Brazil and Thailand are in that range. So is Mexico; all that emigration comes from slow economic growth, not population pressure.

One of the great chicken-or-egg questions is whether antinatalist ideology causes the decline of fertility rates or whether low fertility practices make people amenable to antinatalist ideology. Since Malthus in the 18th century, some people have been saying that population growth causes poverty. The lesson that 19th century economists drew from this hypothetical correlation was that poverty was inevitable, because population would always tend to expand until most people lived at subsistence levels. The correlation was demonstrably false, but that did not prevent busybody 20th century reformers from arguing that poverty could be reduced by reducing fertility rates. The reformers got their wish: the developed world adopted antinatalist policies in the last third of the 20th century. However, this happened after the demographic transition they hoped to engineer had already occurred. Policy will no doubt be a lagging indicator again if higher fertility really is back for a while.

Demographers are worse prophets even than climate forecasters: one correspondent tells me that informed consensus during the New Deal in the United States had it that the country would top out at about 145-million people in the mid-1940s. Nonetheless, we should note that demographers do seem pretty sure that the population of the world will peak late in this century, at around 9 or 10 billion from its current six billion, and then slowly decline. Where would this take us?

Arthur C. Clarke tried to think this through in his novel, Imperial Earth (1976). There he described a world of about 200 million, whose government was preparing to celebrate the 500th anniversary of the American Declaration of Independence. Most people are upper middle class. They move around the essentially borderless world as easily as people move around in their home states today. Everything is spic and span in the world of 2276, including New York City, a truly startling idea when the book appeared. With just 100,000 people, New York is still one of the world's largest cities. All the outer boroughs and northern Manhattan have become forest preserves. Only the Empire State Building remains to represent the age of skyscrapers; it is again the world's tallest building. I remember asking myself 25 years ago what inducement could make people remove the World Trade Center, even if the office space were no longer needed. Ah.

It probably would not work like that. Today there are about 280-million people in the United States. In 1900, there were about 75 million. However, it was in the earlier year that people were more crowded. Even though most people still lived in rural areas, they had less living space in their houses. Cities, of course, were rabbit warrens. Only as population increased did economies of scale make it feasible to build more ample housing and move it out to the suburbs. If there were a billion people in the United States, most of the country, like China today, would still be wilderness. Conversely, as we see in Siberia and parts of the American Midwest today, declining population means that roads are not repaired and public institutions are closed. People have to move closer to the remaining schools and hospitals, not to mention to such jobs as remain in a world of declining demand. Taxes rise per capita. Even solitude becomes less possible as the growing wilderness becomes less accessible.