When lightning sparked the forest fire near Pagami Creek on Aug. 18, U.S. Forest Service officials took a wait-and-see attitude. Because the fire was burning inside the Boundary Waters Canoe Area Wilderness and didn't threaten private property, allowing the blaze to grow was consistent with the "let-burn" policy in the designated wilderness.

Oops. Bad call. Unexpected warm temperatures and high winds fanned the flames. The fire front raced 16 miles in a single day. By mid-September, it had burned nearly 150 square miles and was advancing toward settled areas outside the wilderness.

More than 500 firefighters, including elite hotshot crews, struggled to subdue it. Smoke choked residents in Milwaukee and Chicago. And -- imagine this -- rural citizens with age-old resentment of the federal government grew furious that the Forest Service didn't snuff the fire when it was small.

Perhaps the Pagami Creek fire was destined to become one of the largest wildfires in the wilderness region since the Superior National Forest was created in 1909 -- regardless of decisions the Forest Service made. After all, the summer of 2011 had been painfully dry in far northern Minnesota. Short of cutting down all the trees and creating a suburban landscape of sod and asphalt, there's no way to truly fireproof a forest.

But the Pagami Creek fire is only the most recent in a series of catastrophic blazes that got out of hand, such as the 57-square-mile Ham Lake fire of 2007, and the similar-sized Cavity Lake fire of 2006. The pattern illustrates the weakness of federal fire policy.

More fundamentally, the fires underscore the wrongheadedness of our long romantic fantasy about wilderness.

"Let-burn" is perhaps an unfair name. The policy is more complicated than that. Federal land managers evaluate any fire they learn about on the basis of location, weather and forest dryness to decide whether to snuff it or let it burn for awhile. And to be fair, the Forest Service has shown some management assertiveness by starting "prescribed burns" in the 1999 blowdown area of the BWCA to reduce the tonnage of tangled tree trunks.

But with that exception, the wilderness-area fire policy is rooted in avowed passivity. The Forest Service won't start any fires at all -- even when conditions are favorable -- in a location that would benefit the health of the forest and produce desirable results for wildlife. That would be "unnatural." So, instead, land managers rely solely on fires that start "naturally," by lightning.

The let-burn policy is a retreat from the hard-line firefighting of Smokey Bear of an earlier era. It was an attempt to give the natural ecological force of fire a freer hand in shaping the landscape of the Boundary Waters -- part of a broader philosophy of natural regulation.

Forest fire grooms stands of mature pines. It opens the seeds of jack pines. It regenerates the forest to the benefit of moose, deer, wolves, ruffed grouse and many other creatures. Wildfires have swept this lake country for thousands of years. Some were started by lightning, many by Indians.

But Mother Nature just won't cooperate enough to make let-burn work. Lightning doesn't start fires when and where you want them. Officials can't "let burn" a fire that starts too close to private property. Or when the weather is windy. Or the forest tinder dry. And fires can't sweep in from outside the wilderness, as they did in olden days.

So let-burn is really a "rarely burn" policy. As a result, forest fuels build up and the forest eventually detonates in an explosive conflagration that firefighters try futilely to control.

A more truly natural regimen -- measured against what happened in the past -- would be to prescribe and set intentional fires throughout the forest. But to do that would be to violate our values of wilderness.

Why wilderness is unnatural

Our idea of wilderness as perfectly balanced Nature free from human influence springs from Romantic idealists and transcendentalists. Jean-Jacques Rousseau gave us an Eden where happy primitive man lived uncorrupted by art and science. Thoreau provided a back-to-the-land framework for Romanticism with the declaration that "I went to the woods because I wished to live deliberately." Thomas Moran's paintings of the newly explored American landscape drew their power from the sublime, the juxtaposition of contemporary man with ancient, frightening Nature -- or as it came to be known, wilderness. And Joni Mitchell famously sang of Woodstock, "we've got to get ourselves back to the garden," as though all would then be in perfect harmony.

This romantic conceit collides against reality. "There is nothing natural about the concept of wilderness," writes William Cronon in his essay "The Trouble with Wilderness." "It is entirely a creation of the culture that holds it dear. ... In virtually all of its manifestations, wilderness represents a flight from history."

To create such a place of meditation and worship, the 18th- and 19th-century architects of "wilderness" had to overlook some inconvenient facts -- primarily, the long presence of people on nearly every habitable acre of the continent.

In the case of the Boundary Waters, woodland Indians had lived here and exerted their own influence on the environment since the end of the Ice Age. But Indians were inconvenient, not only to the romantic view, but also to nationalist ones. The first national parks were designated before the dust of Indian wars had settled, with ink still wet on Indian treaties.

It was morally convenient to think of these lands as untrammeled, as though their original inhabitants had never existed. In fact, recent research suggests that before the onslaught of European diseases, Native Americans had numbered in the tens of millions. They hunted, fished and built cities. They managed land and wildlife -- through fire.

As if that weren't enough, the idea of a natural wilderness untouched by human activities makes little sense when people build roads, clear forests, establish communities, and introduce exotic species of plants and animals at its perimeter. And the notion of Nature apart from humans makes no sense at all when humans are changing the very climate in which so-called wilderness exists.

By pretending otherwise, writes Cronon, we "leave ourselves little hope of discovering what an ethical, sustainable, honorable human place in nature might actually look like."

To be specific, our romance with wilderness prevents us from more assertively and effectively managing forest fires through the deliberate use of fire (or even logging equipment), to reduce downed fuel, to clear away diseased stands, to maintain the stands of large pine that people like to see and to improve the forest for certain wildlife species. We forego it all in the name of a mythical balance of unmanaged nature.

Toward gentle intervention

And if today a misbegotten notion of wilderness ties land managers' hands in the Boundary Waters, tomorrow it will stymie other efforts to manage land and wildlife in a changing world and warming climate. If moose disappear from a warmer and grassier Boundary Waters, might it make sense to introduce elk to the region? If a changing climate threatens the existence of native species, should we try moving them to more suitable regions -- even places they never lived in the past? Or if emerald ash borers virtually wipe out native ash trees, might we look to foreign ash trees as replacements?

The pressures of agriculture, population and climate will require rapidly changing policies toward management of the natural world. But if we hew to a wilderness ideal forged by Thoreau and Muir, the answer will always be: We can't.

As ecologist Daniel Botkin writes in "Discordant Harmonies," the belief in perfect harmony in an Eden apart from human involvement is "one of the main impediments to progress on environmental issues. We already play a role and have a responsibility and a capacity to intervene gently on behalf of life."

Or as ecologist and free-thinker Stewart Brand wrote in his iconic Whole Earth Catalog: "We are as gods and might as well get good at it."

Greg Breining writes about science, nature and travel. He is the author of "Paddle North: Canoeing the Boundary Waters-Quetico Wilderness" and "Wild Shore: Exploring Lake Superior by Kayak."