Take at look at Jonathan Last’s very good piece in the Weekly Standard about the real population problem that is confronting the world–people aren’t having enough babies. In America’s One Child Policy, Last explains how fertility throughout the entire world is declining and what the impact will be on society and the economy.

During the last 50 years, fertility rates have fallen all over the world. From Africa to Asia, South America to Eastern Europe, from Third World jungles to the wealthy desert petro-kingdoms, every country in every region is experiencing declines in fertility. In 1979, the world’s fertility rate was 6.0; today it’s 2.6. Industrialized nations have been the hardest hit. America’s 2.06 is one of the highest fertility rates in the First World. Only Israel (2.75) and New Zealand (2.10) are more fertile.

Mr. Last addresses a host of reasons for declining fertility, including some of the politically delicate reasons like education, abortion, and egalitarian social policies that many don’t want to address.

He explains how the one-child policy in China and other small-family campaigns in places like Singapore and Japan have not created the promised “bright future” but serious demographic challenges. And new government policies to reverse the trends are not working.

The Japanese government has been trying to stoke fertility since the early 1970s. In 1972, when Japan’s fertility rate was still above replacement, the government introduced a monthly per-child subsidy for parents….In the face of 35 years of failed incentives, Japan’s fertility rate stands at 1.2. This is below what is considered “lowest low,” a mathematical tipping point at which a country’s population will decline by as much as 50 percent within 45 years. This is a death spiral from which, demographers believe, it is impossible to escape. Then again, that’s just theory: History has never seen fertility rates so low.

As Last and others have reminded us, no country with declining population has ever created widespread prosperity. Perhaps we would do well to remember that the factors of production include not just land and capital, but labor–and labor means people. Decline in fertility will have serious social and economic consequences. Last writes:

At the same time, the average age in China will rise dramatically. In 2005, China’s median age was 32. By 2050, it will be 45, and a quarter of the Chinese population will be over the age of 65. The government’s pension system is almost nonexistent, and One-Child has eliminated the traditional support system of the extended family—most people no longer have brothers, sisters, aunts, uncles, cousins, nieces, or nephews. It is unclear what sort of havoc this atomization will wreak on their society. China will have 330 million senior citizens with no one to care for them and no way to pay for their upkeep. It is, Eberstadt observed, “a slow-motion humanitarian tragedy already underway.”

By 2050, the age structure in China will be such that there are only 1.6 workers—today the country has 5.4—to support each retiree. The government will be forced to either: (1) substantially cut spending (in areas such as defense and public works) in order to shift resources to care for the elderly or (2) impose radically higher tax burdens on younger workers. The first option risks China’s international and military ambitions; the second risks revolution.

Though people still promote Malthusian nightmares of over-crowded planets the real demographic disaster not over-population, but the opposite–not enough babies. This decline in fertility is a prime example of why incentives matter–summed up well in Henry Hazlitt’s definition of economics:

“The art of economics consists in looking not merely at the immediate but at the long effects of any act or policy; it consists in tracing the consequences of the policy not merely for one group but for all groups.”

Acton’s Rome office will be hosting a conference on health care and aging on December 2 at the Lateran Pontifical University in Rome. Get more information here