The U.S. Capitol Building stands past the natural gas and coal fueled Capitol Power Plant, which provides heating and cooling throughout the 23 facilities on Capitol Hill including House and Senate Office Buildings, in Washington, D.C., U.S., on Sunday, June 1, 2014. (Andrew Harrer/Bloomberg)
Opinion writer

There is no denying it: Climate-change deniers are in retreat.

What began as a subtle shift away from the claim that man-made global warming is not a threat to the planet has lately turned into a stampede. The latest attempt to deny denial comes from the conservative American Legislative Exchange Council, a powerful group that pushes for states to pass laws that are often drafted by industry. As my Post colleagues Tom Hamburger, Joby Warrick and Chris Mooney report, ALEC is not only insisting that it doesn’t deny climate change — it’s threatening to sue those who suggest otherwise.

The group, which suffered the highly visible defection of Google because of its global-warming stance and an exodus of other top corporate members, sent letters to Common Cause and the League of Conservation Voters instructing them to “remove all false or misleading material” alleging ALEC questions global-warming theory.

The problem for ALEC is that as recently as 2013, it was still reaffirming “model legislation” calling on states to consider “legitimate and scientifically defensible alternative hypotheses” to the “mainstream scientific positions” on climate. The proposed legislation states that there is “a great deal of scientific uncertainty” about the matter and suggests states treat possible beneficial effects of carbon “in an evenhanded manner.”

The turnabout at ALEC follows an about-face at the Heartland Institute, a libertarian outfit that embraces a description of it as “the world’s most prominent think tank promoting skepticism about man-made climate change.”

But on Christmas Eve, Justin Haskins, a blogger and editor at Heartland, penned an article for the conservative journal Human Events declaring: “The real debate is not whether man is, in some way, contributing to climate change; it’s true that the science is settled on that point in favor of the alarmists.”

Haskins called it “a rather extreme position to say that we ought to allow dangerous pollutants to destroy the only planet we know of that can completely sustain human life,” and he suggested work on “technologies that can reduce CO2 emissions without destroying whole economies.”

To be sure, this is a tactical retreat, and you shouldn’t expect conservative groups to start lining up in favor of a carbon tax. Rather, they’re resorting to more defensible arguments that don’t make them sound like flat-earthers. My Post colleagues quoted energy lobbyist Scott Segal saying that “the science issue just isn’t as salient as it once was.” Instead, Segal talks about the cost and viability of proposed regulations.

It’s likely no coincidence that the shift is occurring as the Obama administration approaches a June target to finalize rules on power-plant emissions. Those who oppose regulation are wise to abandon a position that holds little public appeal; a healthy majority of Americans accept that global warming is real, and a New York Times poll earlier this year found that even half of Republicans support government action to address it.

More and more conservative officeholders are embracing the “I am not a scientist” agnosticism on climate change rather than skepticism. Senate Majority Leader Mitch McConnell, House Speaker John Boehner and presidential candidates Bobby Jindal and Marco Rubio have adopted this response, and Rubio has joined Mitt Romney and Chuck Grassley in embracing the less assailable position that U.S. efforts to restrict carbon are pointless without similar efforts across the globe.

Certainly, figures such as Senate Environment Committee Chairman Jim Inhofe (who calls man-made warming a “hoax”) and presidential candidate Ted Cruz (who fancies himself a modern-day Galileo opposing the “global-warming alarmists”) are not about to change. But as corporations abandon the untenable position of denial, ideologues will be forced to do the same.

As my Post colleagues noted, Southern Co., an operator of coal-fired power plants, decided to drop funding for a Smithsonian scientist who challenged climate-change theory but failed to disclose that his work was funded by fossil-fuel interests. ALEC’s declining skepticism also comes as even oil companies such as Occidental Petroleum and BP quit the group.

At ALEC’s December meeting, a climate-change contrarian got applause for declaring in his presentation that “carbon dioxide is not a pollutant. It is a benefit. It is the very elixir of life.”

For politicians and climate-denial groups, the elixir of life is money. Now that corporations are becoming reluctant to bankroll crazy theories, the surrender of climate-change deniers will follow.

Twitter: @Milbank

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