"How Cities Green the Planet" by Peter Huber and Mark P. Mills, in City Journal (Winter 2000), Manhattan Institute, 52 Vanderbilt Ave., New York, N.Y. 10017.

Follow Portland’s lead and ring America’s cities with "urban growth boundaries" and greenbelts? That’s what some foes of "sprawl" urge. But it’s a bad idea that would result in "less wilderness, not more," assert Huber and Mills, senior fellows at the Manhattan Institute and the Competitive Enterprise Institute, respectively.

Yes, suburbs consume more land than cities do—but rural life eats up even more. City and suburbs should be regarded "as a single economic entity, growing organically together," in their view. "The suburbs wouldn’t exist but for the city and its jobs and money." And the city could not survive without its suburbs as a refuge from its "worst excesses and pathologies." Stop the growth of suburbs, Huber and Mills argue, and you will send the refugees further out into the countryside, just as digital prophets are predicting. Cyberpundit Nicholas Negroponte, for example, foresees the digital world "redistribut[ing] jobs and wealth," with the result being a flow of people "out of, not into, cities."

One of the virtues of sprawl, Huber and Mills argue, is that it saves land. "Cities grow not because they sprawl out from the center, but because they draw people in from the [rural] periphery... far beyond the suburbs."

Over the last three decades, the authors calculate, about 95 million acres of farmland farther from the city "returned to wilderness or began . . . doing so." Some 25 million acres, meanwhile, have been consumed by development—perhaps half of it "farmland that gave way to suburbs."

Today, cities, suburbs, and local roads cover about 27 million acres, and highways a like expanse. The total of 54 million acres— though more than twice the area occupied in 1920—is less than three percent of the two billion acres in the lower 48 states. (Antisprawl activists often also count as "developed land" some 90 million acres of farmsteads, field windbreaks, barren land, and marshland, say Huber and Mills.)

Rural life consumes far more land than suburbia, Huber and Mills argue, and if antisprawl activists ultimately succeed, a wave of Information Age emigrants on new 10-acre farmettes will show us just how much more.