With immigration policy back in the news, I’m reminded that when I was a lad 40 years ago, the cutting-edge wisdom was that rapid population growth was a major problem. (Granted, my parents didn’t let me stay up school nights to watch Johnny Carson, who had Paul Ehrlich, author of the bestseller The Population Bomb, on The Tonight Show about 20 times.) Yet nobody else these days seems to remember the arguments that once struck America’s influential classes as persuasive.

Sure, the doomsayers’ prophecies were overblown, but the notion that moderation in the size of the population has its advantages has hardly been debunked. Nevertheless, the conventional wisdom has simply flipped 180 degrees. That an increase in the quantity of residents isn’t an unalloyed good for Americans is now widely sneered at as some crackpot theory that only hippies on acid would countenance. Everybody knows that a bigger population is Good for the Economy.

In the current immigration debate (if we can call the coordinated marketing campaign we’re being subjected to a “debate”), we are told by Wall Street, academia, corporate shills, and the media that a stable population would be a dire fate. (Not that the US is in terrible danger of that: The number of inhabitants has grown by 34 million in this century.) Thus, illegal aliens are doing us a big favor by coming here to have the children they can’t afford to have in their own countries.

And yet the experts enlightening us about the wonders of a bigger populace don’t seem to be in any hurry for their own communities and colleges to grow. From checking the statistics of elite institutions, you might almost get the impression that the “revealed preference” of people who are good at getting what they want is for very slow population growth.

A lasting inheritance of the 1960s-1970s is an arsenal of environmental, urban planning, and historical preservation regulations that are used by the rich and intelligent to raise the drawbridge behind them. For example, Greenwich, Connecticut is the home of the hedge-fund industry, which I am told has been doing well. Yet from 2000 to 2010, the Census showed Greenwich’s population inching upward by 0.1 percent.

Over that same decade, Beverly Hills, the centerpiece of the entertainment industry, grew ten times faster: 1.0 percent. (In contrast, the entire country increased almost ten percent, and Bakersfield, California mushroomed over 40 percent.)

What about Cambridge, Massachusetts, America’s academic capital? The site of Harvard and MIT increased 3.8 percent in the last decade. Still, Cambridge is smaller than it was in 1950.

The borough of Manhattan, which has been financially booming since the stock market took off in 1982, grew 3.2 percent over the last decade. Yet Manhattan remains about 30 percent less populous than a century ago.

In the intellectual centers of the Midwest, Evanston, IL (home to Northwestern U.) grew 0.3 percent, while Hyde Park (U. of Chicago) fell 14 percent.

Old-money Palm Beach, Florida declined 20 percent.

Even the trendiest city in 21st-century America, Portland, the subject of countless feature articles and a TV show about youngish white people flocking there for the urban hipster lifestyle (”The dream of the 1890s is alive in Portland”), has grown only about as fast as the national average.

What about Red State America? Surely rich Republicans are practicing what they preach?

Somewhat.

Buckhead, “the Beverly Hills of the South,” the north Atlanta neighborhood that was the setting for Tom Wolfe’s A Man in Full, grew 22 percent in the last decade as Charlie Croker-style developers put up more luxury high-rises. Similarly, the population of affluent Plano, outside of Dallas, rose 17 percent.

Yet the two rich Republican enclaves partially enveloped by Dallas”€”Highland Park and University Park (home of SMU)”€”both lost population from 2000 to 2010.