One more comment on this whole libertarian/environment thing. The traditional radical libertarian/ancap response to environmental problems is "sue the polluters."
Turns out more and more environmentalists are doing just that.
Does anyone seriously believe that the Libertarian Party, the Cato Institute, the Mises Institute and all the rest are going to side with the global warming activists? Of course not. And yet, there's no reason--from a strict libertarian standpoint--for them not to. Their creed is being followed to the letter, but their real support goes to pollution over property rights.