Americans consume far more than their fair share of the world’s resources — and more Americans are on the way. The overall fertility rate in the U.S. increased 2 percent from 2005 to 2006, nudging the average number of babies born per woman to 2.1 — high enough to sustain a stable population for the first time since 1971. The U.S. is somewhat of an anomaly, as most developed countries have far lower birth rates (and, to environmentalists’ dismay, are scrambling to raise them). Factors in the U.S. propensity to keep popping kids out may include relatively low use of birth control, widely held religious beliefs that value childbearing, relative ease for women to balance work and family, and a growing population of Hispanic folk. Meanwhile, most developing countries have much higher birth rates — also to environmentalists’ dismay. We’ve got more dismay (and neighbors) than we know what to do with.

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