The Atlantic cover story went on to examine emerging technologies, like solar energy, that lay at the heart of Lovins’s vision. While refraining from outright prediction, the author’s hopes were clear. In 1977, the country appeared poised on the brink of a new age, with recent events having organized themselves in such a way as to make a clean-energy future seem tantalizingly close at hand. A charismatic Democrat had come from nowhere to win the White House. Reacting to an oil shock and determined to rid the country of Middle East entanglements, he was touting the merits of renewable energy and, for the first time, putting real money into it— $368 million.

But things peaked soon afterward, when Jimmy Carter installed solar panels on the roof of the White House. “A generation from now,” Carter declared, “this solar heater can either be a curiosity, a museum piece, an example of a road not taken—or it can be a small part of one of the greatest and most exciting adventures ever undertaken by the American people; harnessing the power of the sun to enrich our lives as we move away from our crippling dependence on foreign oil.”

Now we have our answer: museum piece. In one of the great acts of humiliating political symbolism, Ronald Reagan tore down the solar panels, which spent many years in purgatory before eventually finding their way to the Jimmy Carter Library and Museum in Atlanta, where they sit on display in silent reproach to all who drive Hummers and own high-wattage plasma television sets.

But having mostly followed the hard path since 1977, the world has started to register the dire climatic effects Lovins warned of. The concentration of atmospheric carbon, an important indicator of global warming, has shot from 280 parts per million in pre-industrial times to 386 ppm last year and appears to be accelerating. Most scientists agree that beyond some critical threshold, climate change is irreversible and probably catastrophic. But no one knows just where the threshold lies. The Intergovernmental Panel on Climate Change takes 450 ppm as the benchmark, a level we’re on pace to reach by mid-century—although the prognosis is grimmer than that would imply. Because the effects of atmospheric carbon take years to show up as higher temperatures, limiting concentration to 450 ppm requires halting emissions at current levels. This sudden imperative, coupled with the unlikelihood of action absent a major government intervention, has thrust national energy policy to the forefront of public debate for the first time since Lovins’s heyday.

At least on a rhetorical level, a good portion of the country now seems eager to commit to the soft path. It probably helps that the last administration was synonymous with oil and coal. But last summer’s spike in oil prices gave a nudge even to some who harbored Cheney-esque views of renewable energy. The recent changes in Washington have made a significant shift in the nation’s energy policy a real possibility for the first time in years.