A question we frequently hear is, "Why should we add one more person to an already over-crowded planet?"  The conventional wisdom is that so many new babies are being born that population is threatening to explode beyond control. The conventional wisdom is wrong. What demographers worry more about now is the population implosion that is occurring because of two decades worth of efforts to discourage new births. One of those demographers, Phillip Longman, detailed this problem in an editorial for the USA Today this week:

The U.N. projects that world population could begin declining as early 2040. Those worried about global warming and other environmental threats might view this prospect as an unmitigated good. But lost in most discussions of the subject is the rapid population aging that accompanies declining birthrates.

Under what the U.N. considers the most likely scenario, more than half of all remaining growth comes from a 1.2 billion increase in the number of old people, while the worldwide supply of children will begin falling within 15 years. With fewer workers to support each elder, the world economy might have to run just that much faster, and consume that much more resources, or else living standards will fall.

In the USA, where nearly one-fifth of Baby Boomers never had children, the hardship of vanishing retirement savings will be compounded by the strains on both formal and informal care-giving networks caused by the spread of childlessness. A pet will keep you company in old age, but it is unlikely to be of use in helping you navigate the health care system or in keeping predatory reverse mortgage brokers at bay.

We had the privilege of interviewing Longman about this population reversal for The Boundless Show podcast last year. Longman describes himself as a non-religious progressive who worries that the people who share his views are going to lose the issues of the next generation if they don't get serious about having kids who can be ambassadors of their beliefs in the future.

Longman's warning offers fresh confirmation for the observation our government professor made when we were in graduate school--having babies matters.