The Economist has an interesting look at the policies and programs that have had the biggest impact on curbing CO2 emissions. What strikes me is the first and third most successful programs - you never really hear "Greens" talking about them. Could that be because the Montreal Protocol never would have become a reality without Ronald Reagan? It could be argued that Reagan ended acid rain but what self-respecting tree-hugger would argue that?
The third most successful thing identified to curb CO2 is nuclear power. You almost never hear "Greens" arguing for nuclear power even though one nuclear power plant probably has the same impact as all the Prius' being driven in the country.
It's almost like they'd prefer to see the Earth burn than ever give credit to something Republicans stand for.