Situated on a tall sea cliff above pounding waves, the Diablo Canyon nuclear power plant enjoys the kind of stunning ocean view typical of Central California’s rugged coast. Rolling hills—bright green in winter, fading to gold by summer—surround two Westinghouse reactors that generate electricity for 1.6 million homes. Pacific Ocean waters cool some of the plant’s components. Voles, coyotes, and bobcats roam the meadows and oak glens stretching for miles behind the power station. The sound of the surf obscures any electric hum.

A generation ago, the scene wasn’t as calm. In the late 1970s and early 1980s, Diablo Canyon was at the center of a national grassroots movement against nuclear power. Inspired by the mass protests organized at the Seabrook power plant in New Hampshire, thousands of California residents struggled for years to halt the construction of Diablo, which they said was too dangerous, given that a major geological fault lies just three miles away. In 1977 some 1,500 people demonstrated near the plant to demand a halt in construction; a year later, the number of protesters had tripled. By September 1981 the crowds had swelled to 20,000, and 1,960 people were arrested as they sought to occupy the construction site. It was the largest mass arrest in the history of the U.S. antinuclear struggle.

Today the attitude in the environmental movement toward nuclear power may be changing. Atomic energy, once the bête noir of the movement, is receiving a second look from many dedicated ecologists who are suggesting that, in a world threatened by climate change, splitting the atom may be preferable to burning the carbon. Many people are beginning to wonder: Can nuclear power be green?

Nuclear industry officials, who have long sought to resuscitate their flagging businesses, are eagerly fueling the debate as they seek to position their reactors as a solution to global warming. Nuclear power promoters are feeling more bullish than they have in years. Utilities have filed applications with federal regulators for 32 new atomic reactors, according to the Nuclear Information and Research Service.

The possibility of a nuclear power renaissance is causing strains in the environmental movement as organizations and individuals grapple with the pros and cons of using nuclear power to check carbon emissions. A number of prominent environmentalists—among them Whole Earth Catalog founder Stewart Brand, Pulitzer Prize–winning author Jared Diamond, and Gaia-theory promoter James Lovelock—have come out in favor of atomic energy as a response to climate change. Among mainline U.S. environmental groups, there is near unanimity that nuclear power remains as bad an idea today as it was during the heyday of the Diablo Canyon protests. But at the grassroots level, opinion is split. As one green blogger wrote: “We environmentalists must rethink our opposition to nuclear power. Those who have opposed the building of new nuclear power plants in the United States over the past 20 years have actually forced the use of a filthy alternative—coal combustion—that releases millions of tons of greenhouse gases into the atmosphere.”