Concerns with out-of-control or exponential population growth, and suggested efforts at population reduction, may be missing the mark altogether. It would seem that not only are we not expanding beyond control - the world population is actually declining significantly in the long-term
In the United States, the necessary fertility rate which ensures that the balance of those born and those dying (often called the replacement rate) is maintained, stands at 2.1. In other words, each adult man or woman must be replaced by 2.1 children, if we are to maintain the current world population total. The current fertility rate within the United States, however, which has been below the replacement rate for 25 years, currently stands at 2.0, and is projected to continue to decline.
This is not a trend endemic to the United States - it's actually far worse in other developed nations. The world as a whole has fallen beneath the global replacement rate, from a fertility rate of 5.0 only 30 years ago to 2.7. Within Germany, Italy, and Japan, where it's estimated that by 2050, those over 80 will outnumber those under 20, the rate is far lower. Even in China and Brazil, the replacement rate has fallen under 2.2.
By 2030, it is estimated that the elderly will compose nearly 25% of the total population. In contrast, the elderly made up only about 9% of the population only forty years ago. The inevitable sociopolitical effects of this trend should be self-evident. The elderly, as the principal consumers of govermental health care services, will put an incredible demand upon social systems which will be funded by a correspondingly smaller base of taxpayers.
As an article in the November 2001 Economist points out, the combination of the disproportionately large number of elderly and the shrinking youth populations is a sociological statistic which hasn't occurred since the final days of the Roman Empire. This fact alone should be a cause for significant unease
Markets will change drastically as advertising efforts shift to the middle-aged and elderly, and the economic climate will alter in no less significant ways, since the growth of family structures, which have been the primary market-driving force to this point, will become far less of a motivating factor in commerce. The author of the article also stresses the importance that immigration will take on, especially among the highly educated knowledge workers - including most professionals, university professors, IT specialists, and business executives.
Particularly worrisome is the fact that existing social support mechanisms (like social security in the US) will need to be reformed, but that reform will take place in a political climate increasingly dominated by the interests of the elderly -- who are supported by the very systems that will need to be changed! Anyone familiar with issues in change management can understand that this places a very critical issue within democratic nations into one of the worst categories in terms of resistance to change, asking the people who are dependent upon a system - some for their very survival - to approve initiatives which would make wide-scale changes and re-engineerings of that very system.
This, of course, is not even taking into account the increasing longevity of the race, nor the possible revolutions in medical technology which could significantly affect health and longevity within the next 30-50 years, when we will actually be experiencing the effects of these fertility rates.
It's not necessary for us to consider the fall below the replacement rate, except in the extreme long-term, as a cause for the downfall of society or the surefire path to extinction of the human race! It's perfectly plausable to have a smaller world population - but on the basis of pure statistics, this is the political environment which we who reside in democratic, developed nations will have to overcome if we're to implement social policy which can effectively deal with these realities.
Drucker, Peter, "The Next Society", The Economist, November 2001.