Ben Wattenberg wrote a nice summary of the unprecedented changes in population back in March following the United Nations downward revisions of its population estimates.
Wattenberg wrote,
Now, in a new report, United Nations demographers have bowed to reality and changed this standard 2.1 [total fertility rate] assumption. For the last five years they have been examining one of the most momentous trends in world history: the startling decline in fertility rates over the last several decades. In the United Nations’ most recent population report, the fertility rate is assumed to be 1.85 not 2.1. This will lead, later in this century, to global population decline.
It is startling to realize that the decline in fertility rates has occurred almost as quickly and unexpectedly as did the massive increase in population in the 20th century. As late as the 1960s, Wattenberg points out, total fertility rates in developing countries was averaging 6.0. Today, that average has declined by more than half and rests at 2.9 and still declining.
Once again, the population doomsayers completely underestimated the ability of human beings to modify their behavior for the pure selfish pursuit of self-interest. The same increase in wealth that led to the population explosion also ultimately created economic incentives for couples to limit family size. Once effective contraception, education and other goods reached even less developed nations, people decided on their own (for the most part) to have fewer children.
One area where Wattenberg underestimates the power of people to change is how Europe will face what Wattenberg calls the birth dearth,
Nations with low fertility rates, meanwhile, will face major fiscal and political problems. In a pay-as-you-go pension system, for example, there will be fewer workers to finance the pensions of retirees; people will either have to pay more in taxes or work longer.
No, they’ll likely choose the third option — replace such anachronisms with alternatives (and since people in those countries will likely be even wealthier 50 years from now than they are now, the current political objections to such a solution will likely decrease).
The real danger, which Wattenberg also mentions, is the possibility that the 21st century will end with China and India having huge advantages in population and at best a questionable dedication to liberal values (China, obviously, could remain a dictatorship while India has recently seen a revival of Hindu extremism).
The United States seems likely to maintain its middle road and continued world dominance. Unlike Europe, the U.S. total fertility rate hovers above 2.1 and it continues to accept more immigrants than any other nation. As a a result, the U.S. population will likely increase by another 100 million people in the 21st century.
Source:
It will be a smaller world after all. Ben Wattenberg, New York Times, March 8, 2003.