I grew up in the 1970s, in the first decade of Earth Days, and can recall brief presentations at my Episcopal Montessori (a bit redundant, that) about pollution, recycling, and gas mileage. To be honest, the subject did not interest me very much then or later. I much preferred trying to think globally—or historically and politically—to acting locally. Under pressure from my wife and now my children, I put the newspapers in the right receptacle. Or at least I do most of the time.

I share these not-exactly-earth-shattering domestic details because I suspect many of you are similarly ambivalent about the efficacy of small-scale action to address a planetary problem.

Please hold the e-mails about how the journey of a thousand miles begins with a single step or that it is better to light a candle than to curse the darkness (where would we be without Chinese proverbs?). I stipulate that an individual's sense of responsibility to reality beyond one's self is indispensable to addressing climate change and our dependence on foreign oil. It is just that my lightbulbs and Diet Coke cans are not going to make up for the CO2 pouring forth from China's coal-fired plants.

What might begin to make up for all those emissions is discovering how noncarbon sources of energy could become economically attractive. In a new book that marks an evolution in his thinking, Al Gore, whose Our Choice is the occasion for our cover, recognizes that the debate over climate change can be more about doing well while doing good. As Sharon Begley, who profiles Gore for us, told me, "He is no less concerned about the threat of what he continues to call the climate crisis, but while An Inconvenient Truth had a final section on 'what you can personally do,' this book is much more the analysis of a man who knows that big change comes through political and business activity."

Yes, some people feel a spiritual kinship to being stewards of creation, but in this debate (as in many others) mammon trumps God. Human beings change their behavior only when danger is imminent or when there is money at stake. For many Americans, global warming remains personally remote. Which means that commerce—or, to keep liberals happy, let's call it commerce with a conscience—is our best hope. Energy technology could well be the successor to information technology as the next great engine of economic growth—and we surely need that engine. The trend lines are, thankfully, moving in the right direction: earlier this year the United Nations reported that investments in wind, solar, and other clean technologies were outpacing those in fossil fuels. (The third quarter was bad for green energy, but the third quarter was bad for a lot of folks.)

If investors believe that nuclear, wind, and solar will make them money, then they will get behind the alternatives. If, however, business decides that the bottom line will be best served by talking a good green game but not making significant strides, then we will almost certainly remain mired in a kind of worst-of-both-worlds limbo, knowing we should be doing more to reduce greenhouse emissions but finding the economic cost prohibitive.

For Americans to think of these issues parochially is a mistake: we should invest climate change and its related economic challenges and opportunities with the same diplomatic significance that we historically give more traditional questions. The reasons are obvious, and quantifiable. Much of the estimated increase of carbon emissions between now and 2030 is expected to come from China and developing countries. But those nations are not hopelessly out of touch: the U.N. found that China, India, and other developing nations accounted for the largest part of the new green investments.

The path to energy security, environmental progress, and economic growth is neither short nor smooth nor straight. The global-warming true believers who want instant results are destined to be disappointed, and the deniers who try to undermine the scientific consensus or the skeptics who cynically say large-scale change is politically, economically, and culturally impossible are being unhelpful.

Though he is the PowerPoint prophet of the left, the Oscar-winning former vice president is emerging as a more realistic voice. He was almost the 43rd president (think of him as 42.5). Now the 44th should read his book, and learn from it.

Jon Meacham is editor of NEWSWEEK and author of American Lion: Andrew Jackson in the White House and American Gospel: God, the Founding Fathers, and the Making of a Nation .

© 2009