Has the green movement been a miserable flop?

What the hell went wrong? For months now, environmentalists have been asking themselves that question, and it’s easy to see why. After Barack Obama vaulted into the White House in 2008, it really did look like the United States was, at long last, going to do something about global warming. Scientists were united on the causes and perils of climate change. Al Gore’s An Inconvenient Truth had stoked public concern. Green groups in D.C. had rallied around a consensus solution—a cap-and-trade program for carbon emissions—and had garnered support from a few major companies like BP and Duke Energy. Both Obama and his opponent, John McCain, were on board. And, so, environmental advocates prepared a frontal assault on Congress. May as well order the victory confetti, right?

Instead, the climate push was … a total flop. By late 2010, the main cap-and-trade bill had fizzled out in the Senate; not a single Republican would agree to vote for it. Greens ended up winning zilch from Congress, not even minor legislation to boost renewable electricity or energy efficiency. Worse, after the 2010 midterms, the House GOP became overrun with climate deniers, while voters turned apathetic about global warming. All those flashy eco-ads and all that tireless eco-lobbying only got us even further from solving climate change than we were in 2008.

So now greens are in the post-mortem stage, and, not shockingly, it’s a sensitive subject. On Tuesday, Matthew Nisbet, a communications professor at American University, released a hefty 84-page report trying to figure out why climate activism flopped so miserably in the past few years. Nisbet’s report is already causing controversy: Among other things, he argues that, contrary to popular belief, greens weren’t badly outspent by industry groups and that media coverage of climate science wasn’t really a problem. And he raises questions about whether greens have been backing the wrong policy measures all along. Is he right? Have environmentalists been fundamentally misguided all this while? Or were they just unlucky?

Just about everyone in the green movement has a theory for why the climate fight sputtered out. Some activists blame their all-too-powerful foes. The oil and coal industries, as well as groups like the National Association of Manufacturers, all vehemently opposed cap-and-trade and shelled out millions lobbying Congress. The cranks who deny that global warming is manmade were way too effective at spreading their disinformation. And gullible reporters were too willing to give these skeptics airtime. Call this the “we were outgunned” theory. Bill McKibben, for one, has argued that enviros need to spend more time targeting the “the guys with the money who pull the strings,” like the Chamber of Commerce and the Koch brothers. Some climate scientists, meanwhile, have argued that they need to get better at swatting down gibberish from the skeptics. Shortly after the midterms, some 40 climatologists around the world banded together to form a “rapid response unit” on key climate-science questions. (It’s still too early to judge the end result.)

Then there are the lefty greens—groups like MoveOn.org and Friends of the Earth—who have long argued that the inside-the-Beltway strategy of 2009 and 2010 was inherently self-defeating. The mainstream green groups, these lefties argue, spent way too much time compromising with fossil-fuel interests in order to craft a byzantine cap-and-trade proposal that could placate enough swing voters in Congress. The end result was too loophole-ridden and too complicated to excite the base. Call this the “no one likes a sellout” theory—it’s the idea that a simpler, stronger policy (say, a flat carbon tax), combined with fervent grassroots pressure, might have stood a better chance.