Republicans struggle to find a convincing reason not to take action on climate change, so they tend to recycle excuses. In the 2014 election, one line in particular caught on—the two top Republican congressional leaders, Mitch McConnell and John Boehner, insisted they were not qualified to discuss climate change science because they were not scientists. Since then, countless high-profile figures have called out this line, including President Barack Obama and Stephen Colbert.

But “I’m not a scientist” has fallen from favor in the GOP, perhaps because it polls terribly. Another very old meme is resurfacing to take its place. 

Former Pennsylvania Senator Rick Santorum demonstrated the line in a speech on Thursday. Santorum, who uses his religion to justify policies such as discriminating against gay people and outlawing abortion in all circumstances, accused President Barack Obama of being motivated by the so-called religion of environmentalism. “[Obama] is against fossil fuels, for his own, in my mind, quasi-religious reasons, which is not a rationale," Santorum said. "If someone would go forward and put forth a religious idea as to how we should regulate the environment, and it was based on a Christian or other types of religious (ideas), they would be condemned up and down." 

Similar remarks seem to be circulating within the GOP. 

Earlier this month, Senator Johnny Isakson of Georgia juxtaposed climate change and religion on the Senate floor, while he misrepresented the scientific evidence. “I believe the climate does change, but I don’t believe climate change is a religion," he said. "I think it’s science. I’ve done everything I can as a United States Senator to educate myself on the carbon issue and the climate change issue. Seven years ago I went with Senator Boxer from California to Disko Bay in Greenland with Dr. [Richard] Alley, who’s the leading glaciologist in the world, to study for a while what he says about carbon being the cause of climate change. And there are mixed reviews on that and there’s mixed scientific evidence on that.” 

Even South Carolina Senator Lindsey Graham, one of the Senate’s few Republicans willing to acknowledge climate change exists, made the dogmatic comparison in a speech last week: “The problem is Al Gore's turned this thing into religion."

Graham, exceptionally for a conservative, accepts the reality of human-caused climate change. He considers it to be an economic problem (as do advocates for climate change action, generally) and urges the GOP to find a more sensible platform. “You know, climate change is not a religious problem for me," he added. "It's an economic—it is an environmental problem." 

Republicans, even Graham, who compare climate change to a religion typically do so to push back on Obama's executive action limiting carbon pollution. What better way to make Obama look extremist than claim he is being motivated by a religious fervor for environmentalism?

The climate-as-a-religion accusation is hardly a new invention. It continues to cycle in and out of political rhetoric. The late sci-fi writer Michael Crichton (Senator James Inhofe’s favorite climate change expert) elevated it in a 2003 speech the Wall Street Journal reprinted on March 15. He declared that “one of the most powerful religions in the Western World is environmentalism.” Inhofe, who uses the Bible to refute climate change science, repeated these words in 2005 remarks on the Senate floor. He said, “Put simply, man-induced global warming is an article of religious faith.” Countless others have picked it up since then. 

Conservatives have long tried to discredit the scientific consensus on climate change by arguing, for instance, that there's a global warming "hiatus" and by attacking climate scientists. But they're increasingly aware that they can’t win a debate in the realm of science. So rather than try to discredit the scientific consensus, they're reframing a discussion about hard data into one of faith—just as they've done in their war on evolution. If climate change is merely a faith—something one choose to "believe" in—then climate change deniers can claim they are the ones motivated by reason.

Environmental Protection Agency Administrator Gina McCarthy gave a blunt answer to Republicans arguing this at a congressional hearing earlier in March. “Climate change is not a religion,” she said. “It is not a belief system. It’s a science fact.” Taking action to mitigate and adapt to global warming isn't a faith-based task. It is a response to reality. Obama is responding to an issue that affects the businesses, the weather, infrastructure, agriculture, insurance market, GDP, medical care, and more. This isn’t about his personal "belief" about coal. Republicans can disagree with Democrats about the best solutions to pursue, but they can’t reasonably argue that not responding at all is an option.