THIS WEEK, The Sun editorial page featured an excellent series promoting Smart Growth, making a compelling case for checking the sprawl development that is needlessly trashing the Chesapeake Bay region's remaining natural landscapes.

Yet the series makes a very flawed assumption - all the more troubling because the same assumption is made, implicitly if not overtly, by nearly every environmental organization in this nation:

"Growth is inevitable - and welcome," says the editorial, as if to reassure: "Hey, we may oppose current patterns of development, but we're not crazy no-growthers."

It's the deadliest kind of reassurance. It endorses truly valid prescriptions for righting environmental wrong, like Smart Growth.

Simultaneously, it grants license to continue ignoring population growth - which every study that has ever looked at the root causes of our environmental problems, including sprawl development, identifies as a major driving force.

Growth is inevitable - and welcome.

Certainly growth is not inevitable. The United States is the only major industrialized country in the world where large-scale population growth is happening.

Among 14 other industrialized nations, from Japan to Europe to Scandinavia, all but one (Norway) have birth rate and immigration trends that would be more than adequate to stabilize the U.S. population in coming decades.

Also, a major component of U.S. population growth - foreign immigration - has more than tripled from its historic average in recent decades, through acts of Congress. And acts of Congress could reduce it again.

Growth is inevitable - and welcome.

I suspect growth is more tolerated than welcomed by the majority of Americans. It will become less tolerated the more our environmental leaders and managers become honest about the prospects of restoring and sustaining our natural resources as a million new people every decade move into regions like the Chesapeake watershed.

Concurrent with that, we need economists who will re-examine the common wisdom that economic well-being is inextricably linked to ceaselessly growing numbers of consumers.

As recently as 1972, a bipartisan Congressional Commission on Population Growth and the American Future examined these issues and concluded:

"We have looked for, and have not found, any convincing economic argument for continued population growth. The health of our country does not depend on it, nor does the vitality of business nor the welfare of the average person ... rather, the gradual stabilization of our population would contribute significantly to the nation's ability to solve its problems."

Has that situation changed since 1972? Not according to Edwin Stennett's just-published In Growth We Trust, a highly recommended examination of Smart Growth and population growth in the Chesapeake region. It's available for $12.95, including shipping, from the nonprofit Growth Education Movement, P.O. Box 2876, Gaithersburg, MD 20886.

Stennett finds that about two-thirds of open space being developed in the D.C. metro region is a consequence of increasing population. Increased per-capita use of land for housing, the "sprawl" typically targeted by Smart Growth, is only about a third of the problem.

He demonstrates that even the strictest conceivable application of Smart Growth strategies, given continued population increase, will only delay the losses of open space by a few decades.

Similar studies of sprawl by Numbers U.S.A., a Washington-based nonprofit that works to stabilize U.S. population, show population growth, per se, is about half the problem in sprawl.

Stennett also makes a good start at separating population growth from economic well-being. He notes a Brookings Institution study, for example, that found population growth is not related to per-capita income in the Washington region.

The point is not that Smart Growth isn't worth pushing for all its worth. Altering the ways we live is critical.

Americans' lifestyles require almost twice as many of the planet's acres to support them as lifestyles of the average German or Frenchman; and we generate triple the carbon dioxide of the average Swede, hastening climate change.

But working on half the problem - how we live - while pretending it doesn't matter how many of us live here, will not likely achieve ambitious goals such as restoring the Chesapeake Bay.

Stabilizing population is a tough and complex issue, to which no one has all the answers. But to unthinkingly shrug off growth as "inevitable - even welcome," while promising an improved environment, is irresponsible and ultimately dishonest.