The Most Overpopulated Nation

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The Most Overpopulation Nation
An NPG Forum Paper
by Paul R. Ehrlich and Anne H. Ehrlick
January 1991

This paper was originally published by NPG in January 1991.
We are reprinting it 5 years later, in November 1996, with the Ehrlichs’ permission.

Those of us who deal with population issues all the time are frequently confronted by people who believe the population problem belongs to someone else. It traces, in their view, to poor Indians who do not understand how to use condoms, or to Mexican peasants who invade our country to steal our jobs, or to the Catholic hierarchy which persists in its irrational opposition to the use of effective birth control methods. But Indian peasants mostly want the children they have – they know how to use condoms. And at the moment Mexican immigration is probably a net benefit for the United States – although in the middle term it could become a disaster. And crazy as the Vatican’s position is, relatively few Catholics pay any attention to it. After all, Italy has the smallest family size in the world!

But it just does not wash. Yes, poor nations have serious population problems, but in many respects rich nations have worse ones. Nothing recently has made the degree of overpopulation in the United States more obvious than George Bush’s confrontation with Iraq. If the United States had stabilized its population in 1943, when it was in the process of winning the largest land war in history, today it would just have 135 million people. Assume that per-capita energy consumption nevertheless had grown to today’s level – that is, our smaller population was still using sloppy technologies: gas guzzling automobiles, inefficient light bulbs and pumps, poorly insulated buildings, and so on. Even if its citizens were just as profligate users of energy as we are, the 135 million United States citizens could satisfy their energy appetite without burning one drop of imported oil or one ounce of coal.1

Of course, if we had been smart, we also would have become energy efficient and would have made a transition to some form of solar-hydrogen economy. It has been estimated that an energy efficient America could have the goods now supplied by energy use at an expenditure of about one-third the energy now employed. And it is crystal clear that for the environmental health of the globe as a whole, and the United States itself, a drastic reduction in the use of energy technologies that place greenhouse-enhancing carbon dioxide into the atmosphere is mandatory.

I = P A T

The impact of a population on the environment can be roughly viewed as the product of three factors: the size of the population (P), the level of per-capita consumption or affluence (A), and the measure of the impact of the technology (T) used to supply each unit of consumption. This provides the short-hand equation I=PxAxT which, although oversimplified (because the three factors P, A, and T are not independent), provides a basis for comparing the responsibility of different nations or groups for environmental deterioration.

Using the I = P A T equation, one can see that the population problem in the United States is the most serious in the world. First of all, the P factor is huge – with 250 million people, the United States is the fourth largest nation in the world. And compared with other large nations, the A and T factors (which when multiplied together yield per capita environmental impact) is also huge – on the order of twice that of Britain, Sweden, France, or Australia, fourteen times that of China, forty times that of India, and almost 300 times that of a Laotian or Ugandan. In per-capita energy use, only a few oil producing nations in the Middle East such as Qatar and Bahrain, plus Luxembourg and Canada, are in our league, and those nations have comparatively tiny populations. When the population multiplier is considered, the total impact of the United States becomes gigantic, several hundred times that of Bangladesh.

Those multipliers are based on per-capita commercial energy consumption, which is the best surrogate for A x T that is readily found in government statistics. The contributions of very poor countries to environmental deterioration are underestimated by these statistics, since they don’t include the impacts of use of “traditional” energy sources (fuelwood, dung, crop wastes) that comprise 12 percent of energy use globally, but a much larger component in poor countries. Considering them would not change the U.S. position as the planet’s primary environmental destroyer, though.

That preeminence makes sense intuitively, too. Few Laotians drive air-conditioned cars, read newspapers that transform large tracts of forest into overflowing landfills, fly in jet aircraft, eat fast-food hamburgers, or own refrigerators, several TV’s, a VCR, or piles of plastic junk. But millions upon millions of Americans do. And in the process they burn roughly a quarter of the world’s fossil fuels, contributing carbon dioxide and many other undesirable combustion products to the atmosphere, and are major users of chlorofluorocarbons, chemicals that also add to the greenhouse effect and attack Earth’s vital ozone shield.

We have destroyed most of America’s forest cover (replacing a small fraction of it with biologically impoverished tree farms) and are busily struggling to log the last of the old growth forests in the Northwest, threatening the long-term prosperity of the timber industry, in part to service the junk bonds of rich easterners. The western United States is one of the largest desertified areas on the planet from overgrazing by cattle and sheep – not because we need the meat (only a small portion of our beef comes from the arid West), but because of the political power of ranchers in the western states and a nostalgic view of western history. And Americans have contributed mightily to the destruction of tropical forests by purchasing products ranging from beef to tropical hardwoods derived from forests….Continue reading the full Forum paper by clicking here.