ACROSS the world, doomsayers are smiling. The mounting signs of climate change have forced onto center stage the challenges of reducing carbon emissions and quickly adapting human activities to thrive in higher temperatures and more unpredictable weather.

Alas, the bad news about climate change is good news for business.

A curious feature of capitalism is that threats, or more precisely, the human response to them, are economically and technologically stimulating. Or, to put it another way, ''Necessity is the mother of invention.''

There will always be doomsayers, and fantasies about the end of human society are a staple of Hollywood and science fiction. But these days, a lot of smart people are seriously contemplating the looming destruction of human society, whether through a cascade of natural disasters, nuclear wars, uncontrolled terrorism, novel pandemics or, of course, climate change.

Because I attended the Woody Allen school of futurism and generally find humanity poised between the horrible and the terrible, I always remember the childhood story of the boy who cried wolf. Cry too often about ill-formed threats and you lose all credibility.

But there are good reasons to believe that crying wolf is exactly what the brightest innovators ought to be doing, and not only in response to the challenge of climate change. As a general matter, high anxiety will lead to more intense pursuit of innovation.

In the history of economics, the ultimate wolf-crier was Joseph A. Schumpeter. An Austrian economist who taught at Harvard, Mr. Schumpeter in 1942 coined the term ''creative destruction'' to describe what he viewed as the engine of capitalism: how new products and processes constantly overtake existing ones. In his classic work, ''Capitalism, Socialism and Democracy,'' he described how unexpected innovations destroyed markets and gave rise to new fortunes.






Mr. Schumpeter brilliantly realized that innovation -- so often extolled as the purest expression of the human spirit -- has a dark, violent, even nasty side.

Every innovator, in short, makes a declaration of war. And every successful innovation is a destroyer.

To be sure, in these wars only technologies die, not the people who stand behind them. Yet people suffer nevertheless.

Richard W. Fisher, president of the Federal Reserve Bank of Dallas, said in a speech last month that he knew firsthand of ''the painful adjustments that economic advancement inflicts upon displaced workers.''

''I grew up in a household where my father suffered more than his fair share of the destructive side of that process,'' Mr. Fisher said. ''It was difficult for him to grasp the allure of the creative side of the equation, and I am more familiar with the anguish that comes when a breadwinner loses his job.''

Mr. Fisher dwelled on the anguish felt by the losers in technological battles to point up the need for government and society to treat the losers with compassion. Yet liberal impulses to both embrace the new and assist those swept aside by technological change ignore an enigma: that destruction itself is often liberating, unleashing waves of innovation.

Even all-out war can lay the seeds of creative destruction. The leveling of Germany and Japan at the end of World War II forced the rebuilding of factories in those countries with the latest technologies, catapulting them into the first ranks of industrial powers.

In addition to wiping out old physical structures, wars can obliterate old intellectual and organizational structures that restrain innovators.

''Violence breaks old relationships and upends people in power,'' says Joel S. Migdal, a professor of international studies at the University of Washington. ''Once these structures and people are swept away, all sorts of things can happen.''

Economic growth isn't guaranteed after an all-out war, naturally. Liberia and Sierra Leone are proof of that. But the hope that creation can follow destruction is motivating the leaders of Rwanda, where the 1994 genocide wiped out the country's social networks. Rwandans are supporting a range of initiatives, like new universities, a movie-making center and investments in technology from companies like Google, that they hope will promote an innovative economy based on creativity.

WAR, of course, is only the most dramatic form of destruction. In the case of climate change, humanity faces a hydra-headed threat, where the risks remain hard to identify with precision and the costs, at least for now, are borne chiefly in the poorest parts of the tropics.

Until recently, environmental wolf-criers emphasized the need to reduce emissions drastically, thus ensuring stability for human communities at some date in the future. Now experts are increasingly convinced that new technologies are widely and urgently needed, including drought-resistant crops, more efficient uses of water, new sources of energy and new building materials.

These new technologies, publicized by wolf-criers and driven by the impulse for self-preservation, will ultimately supplant existing products and processes -- and remind us anew that the pursuit of innovation is the moral equivalent of war.

Drawing (Drawing by Christophe Vorlet)