One explanation is that the framing of environmental issues is often anathema to conservatives. Matthew Feinberg and Robb Willer’s important paper on the subject, “The Moral Roots of Environmental Attitudes,” finds that liberals view environmental issues as moral concerns informed by a harm principle, while conservatives view environmental issues through the lens of purity, and particularly for religious people, stewardship.

In 1971’s Octogesima Adveniens, Pope Paul VI laid out a religious case for protecting the environment, using the language of responsibility, duty to future generations, and purity—in other words, the conservative framing under Feinberg and Willer’s standards:

Man is suddenly becoming aware that by an ill-considered exploitation of nature he risks destroying it and becoming in his turn the victim of this degradation … thus creating an environment for tomorrow which may well be intolerable .... The Christian must turn to these new perceptions in order to take on responsibility, together with the rest of men, for a destiny which from now on is shared by all.

In his 2006 “Letter to a Southern Baptist Pastor,” E.O. Wilson showed how to use the religious framing in defense of the environment:

You have the power to help solve a great problem about which I care deeply. I hope you have the same concern. I suggest that we set aside our differences in order to save the Creation. The defense of living nature is a universal value. It doesn’t rise from, nor does it promote, any religious or ideological dogma. Rather, it serves without discrimination the interests of all humanity. Pastor, we need your help. The Creation—living nature—is in deep trouble.

The environmental movement has stumbled because it has not framed the issue as Wilson and Paul VI did. A 2012 study by Matthew C. Nisbet, Ezra M. Markowitz, and John E. Kotcher found that climate campaigns overwhelming frame the issue in terms of harm and care, fairness, and oppression of marginalized groups. These frames fall into what Feinberg and Willer would consider left-wing frames, alienating conservatives.

Adopting a more conservative framing wouldn’t lead to liberals winning more elections. More likely, moderate Republican and centrist thought leaders could make green policy a bipartisan initiative of the sort that was common during the Eisenhower, Nixon, and Bush Sr. days. There are already right-leaning pro-environment groups, like Atlanta’s Green Tea Coalition and Ducks Unlimited. That’s unlikely to be enough to bridge the divide. Because people are more likely to respond to arguments made by someone within their community than outside of it, progress depends on more Republican voices.

But Republican thought leaders and policymakers have abandoned the environment in droves. ThinkProgress calculates that 56 percent of Republicans in the current congress deny anthropogenic global warming. Among the general public, 26 percent of adults don't believe global warming is real (although only 11 percent of Democrats do, versus 46 percent of Republicans and an astonishing 70 percent of Tea Partiers). Deborah Guber, a professor at University of Vermont, argues that there has been a concerted effort among right-leaning elites to downplay the environmental issue. “Partisan conflicts are not inherent in the subject of climate change,” she writes. “Party sorting seems to occur only as citizens acquire information and become familiar with elite cues.” This helps explain the lack of political movement, despite evidence that conservative voters are concerned about the degradation of the environment.