After a climate bill fizzled out in the Senate last year and Republicans won big in the midterms, many observers wondered how the environmental movement could reinvent itself. Would it shift to playing defense on the EPA? Try to build a broader grass-roots movement? But few could have predicted the trend we’re seeing now: Amid calls for austerity, some green groups are aligning with conservative think tanks to push for cuts to environmentally harmful programs.

The odd alliance kicked off last month when Friends of the Earth and Public Citizen teamed up with Taxpayers for Common Sense and the conservative Heartland Institute for their “Green Scissors” report, focusing on cuts to everything from ethanol and oil tax credits to timber subsidies. And this month? The Natural Resources Defense Council (NRDC) is teaming up with the libertarian Reason Foundation and Taxpayers for Common Sense to attack the Essential Air Service program, which has been a small but controversial part of the ongoing fight over FAA funding in Congress.

It’s easy to see why small-government types don’t like the Essential Air Service. The program spends nearly $200 million annually to fund flights to 153 small airports around the country — flights that would otherwise be uneconomical. The green argument, meanwhile, is that these flights put a lot of carbon dioxide into the air and that, in some cases, the routes could be covered more cheaply and cleanly if the government instead subsidized bus shuttles between these rural communities and nearby airport hubs. Obviously there aren’t alternatives to many flights in Alaska or Hawaii, say, but there are at least 38 communities within 150 miles of a major airport.

So the groups commissioned an analysis by M.J. Bradley & Associates to see what would happen if these towns were served by bus-shuttle service instead. A flight from Altoona, Pa., to Dulles airport in Washington, for instance, could be swapped out for a bus route for half the cost. True, the buses would take more time — about 43 minutes longer, on average — but ticket prices would be far cheaper. All told, taxpayers would save about $50 million a year, and the reduction in pollution would be sizeable:

“We’ll be doing a lot more of this kind of analysis,” he added, noting that, in a capital gripped by deficit-curbing fever, “it’s a substantive and political sweet spot.”