Sitting in for Andrew Sullivan Patrick Appel joined Krugman in wondering why Greenpeace is opposing the Waxman Markley bill, America's first effort at a proper climate policy. It is, goes the argument, the best deal on the table, what else are you going to do?

Well, we've never been great ones for compromising when it comes to doing what's best for the environment. And what's best for the environment is a global deal that commits the world to significant emission cuts. As I wrote below, if the opening bid from one of the world's biggest polluters is a cut of zero, well, that's just not going to cut it.

We're running out of time. This isn't the kind of issue where you can make incremental progress year on year, and arrive at a victory decades after you started. Not anymore. The climate system is full of tipping points which could make climate change unstoppable and irreversible and we're sleep walking toward them. The best chance to avoid catastrophic climate change is this year, at the climate summit in Copenhagen, and now our hopes are being sold out to a handful of tame politicians kept by the industries that caused this problem.

And we're supposed to accept this in the name of pragmatism? Right now the world needs America to sign up to climate legislation that will help the world turn away from catastrophe. When this bill passes America will still need climate legislation that will help the world turn away from catastrophe and we'll still be campaigning for it. No-one should kid themselves that this bill will solve the problem. That might not be what people want to hear, just one more inconvenient truth to add to all the others, but there it is.

Obama promised the world a climate policy based on science - well, Mr President, we're still waiting.