There is a population crisis at the end of the 20th century. It's just not the one you've been hearing about.

Two recent reports, one from the United Nations and the other by France's National Institute of Demographic Studies, tell a dramatic, disturbing story:

• There are 185 countries in the world; 51 of them are committing slow-motion demographic suicide because they have below-replacement-level birth rates (less than 2.1 children per woman).

• Italy, Germany, Russia, and 10 other countries are suffering a “negative population balance,” or, to skip the euphemism, depopulation. Why? Not because of war, plague, or famine, but because of low birth rates. Italy has the world's lowest birth rate.

• The trend toward below-replacement-level birth rates has spread beyond the developed “First World” into Eastern Europe, Asia, and the Caribbean.

The vice president of the United States, fretting about “global warming” recently, complained that there were “too many people” on the planet. The fact is that in many societies, including some of the world's wealthiest, there aren't enough people.

France and Germany are two cases in point. Both have severe social problems because of “guest workers” or immigrants from North Africa and Turkey. The depopulated Franco-German core of the European community has become a demographic vacuum, which is quite naturally being filled by peoples migrating across the Mediterranean—in the age of jet aircraft, a river rather than a sea. And the French wonder why they have a French identity problem in their schools?

George Weigel

Is it an accident that Western Europe is becoming depopulated at the same time as the continent sinks deeper into secularization? I think not. Western Europe today is more stable, peaceful, and prosperous than at any time in recorded history. Yet its people refuse to reproduce themselves. This suggests a profound crisis in cultural morale.

Historically unprecedented standards of living and increasing life expectancy ought to create conditions conducive to at least maintaining one's population, if not increasing it. Yet the opposite is happening in Western Europe. Why? Because too many Western Europeans suspect that life is not worth transmitting? Because too many Europeans are too obsessed with consuming to take on the responsibilities of procreation and education?

Whether the cause is anxiety about the future or greed in the present, de-Christianization and depopulation have gone hand-in-hand in Western Europe in the late 20th century.

The ideology of population control has also shaped today's alarming depopulation trends.

For decades, International Planned Parenthood and its national and local affiliates have held the cultural high ground in the developed world. They continue to do so, despite overwhelming empirical evidence that contradicts Planned Parenthood's claims about world “over-population.” The endless repetition of that claim has, in turn, profoundly shaped—no, warped—the way too many people think.

Why is it that, when a calf is born in a poverty-stricken African country, everybody thinks, “That's a resource,” but when a child is born there, too many Americans think, “That's a problem”?

If enough people are constantly told that children are a problem, if that message is reinforced through a host of cultural enticements and pressures, and if the technology is available to act on the message, the result, absent a countervailing moral force, is predictable: the number of children in that society will be drastically curtailed. And the result of that, over several generations, is depopulation.

The Catholic Church has tried to be that countervailing moral force, but with decidedly mixed results. Too many Catholic leaders—ordained and lay—have been cowed into thinking that the Church's ethic of marital chastity cannot be successfully proposed or defended. Yet in John Paul II's book The Theology of the Body, which describes marital love as an icon of the inner life of the Trinity, the Church now has the most compelling account of human sexuality on offer in the developed world. Isn't it time to regain our nerve on this front—beginning by regaining our wits?

Two predictions. On its 30th anniversary this summer, Paul VI's encyclical, Humanae Vitae, will be pilloried yet again, by prominent Catholics among others. On its 60th anniversary, Humanae Vitae's challenge to the contraceptive mentality will be recognized as a prophetic warning against the demographic implosion of the West.

George Weigel is a senior fellow of the Ethics and Public Policy Center in Washington, D.C.