And because many of us didn’t have—or had fewer—kids, we’re now told that we need mass immigration to make up the shortfall.

In conclusion, Ehrlich warned that “sometime in the next 15 years, the end will come,” meaning “an utter breakdown of the capacity of the planet to support humanity.”

If these musings had been received for what they actually were—the wacky theories of a crackpot academic—all would have been well. But The Population Bomb sold some 3 million copies and influenced an entire generation.