Global warming is not just another issue in a long line of environmental problems that have received attention starting with Earth Day 1970. With honor and respect to all the great environmental victories, and to the people who fought for them, we feel that global warming will take a revolution in the way we see ourselves.

Adequately confronting global warming will require as much change from us as was required during the transition to the industrial revolution. We must, in effect, learn to live in a whole new world.

While there is still much uncertainty about how global warming will impact the earth, we know enough now to start the journey to sustainability. Evidence of global warming is sufficient to hold policymakers guilty of public-policy malpractice if they fail to act immediately and vigorously. History’s judgment will be harsh on those who ignore such clear warning signs.

Our oceans are warming, our ice caps and glaciers are melting, our soils are eroding, our rainforests are shrinking, our ocean coral is dying, our fisheries are being depleted, and more and more species are disappearing. We are told by the National Academy of Sciences, the Royal Society and by most of the living Nobel Prize winners that global warming is a reality that we must take seriously. Even the Pentagon, hardly a historic voice for the environment, has issued a report, "An Abrupt Climate Change Scenario and Its Implications for U.S. National Security," laying out a series of possible nation-threatening scenarios for global warming.

How can anyone read these reports and return to business as usual? Perhaps because the implications to our everyday lives are so immense that we’d rather not comprehend them. One reason the attack on 9/ll succeeded was that the possibility of crashing planes into skyscrapers was almost beyond imagination.

Likewise with global warming: Trying to imagine a world without growing petroleum use, or traditional ways of growing the economy, or where human population must shrink rather than grow comes close to the unimaginable. Historian Barbara Tuchman observed how hard it is for those in charge to react to new realities: "When information is relayed to policymakers, they respond in terms of what is already inside their heads and consequently make policy less to fit the facts than to fit the baggage that has accumulated since childhood."

It is also immensely difficult to see our individual place within the ecological whole. The most cited article in the history of Science magazine helps us understand why. Garrett Hardin’s "The Tragedy in the Commons" concluded that when natural resources are held in common, free and available to all for the taking, people steadily increase their exploitation of the common resources until they are exhausted. Every participant in the tragedy pleads "not guilty." But the entire system moves toward disaster.

The poet W. H. Auden wrote, "All life is the question of whether or not to have children, after you’ve already had them." It is hard for us to see how our automobiles, our airplane travel or our third or fourth child will affect the environment when they bring us so much pleasure, but the impact is shared worldwide.

We do not recognize the lifetimes it takes to correct environmental damage or to reverse the damage already done. So it is a surprise to realize that the exhaust from President Kennedy’s automobile on the day he was assassinated still hasn’t fully played out its environmental impact. It takes perhaps 60 or 70 years for today’s pollution to reach full impact as greenhouse gases. Like a car braking down, it will take us a significant and perhaps fatal amount of time to brake down our industrial society. It will require foresight not historically present in humankind.

What we treat as just another environmental issue is more accurately a clash of civilizations. It is the shift from identifying individual polluters to be stopped to the issue of all of our lifestyles. We can only observe how nearsighted it is that so many people today focus on cultural and religious differences between the West and Islam, when human civilization itself stands on the brink of collapse.

Is it naive to hope that — like the appearance of an earthbound asteroid or the invasion of extraterrestrial aliens in all those countless, trite science fiction films — global warming may be the common cause that finally unites the human enterprise? Whatever it takes, we must begin to focus on the one environmental issue that threatens us all.

Richard Lamm and Buie Seawell are contributors to Writers on the Range, a service of High Country News (hcn.org). Both are professors at the University of Denver, Lamm in public policy, and Seawell in business.