Diplomatic anxiety about the Copenhagen climate summit is reaching fever pitch. UN Secretary Ban Ki-moon has issued an urgent warning that the talks are stalled; UN development chief Helen Clark is already engaged in damage control and lowering expectations. Ed Miliband, the British climate change minister, is shuttling around the world to try and oil the wheels ahead of next week’s New York meeting. What’s at the root of the problem? There’s the long standing tension between rich and poor countries: the rich don’t want to take responsibility for their expensive life styles, the poor don’t want the ladder pulled up while they’re still on the ground. There’s China and its coal plants. And then there’s You Know Who.

The front page of this morning’s Guardian trumpets an exclusive: news of a fracas between European and US negotiators about the shape of the treaty to be negotiated. Man Bites Dog, perhaps; but it’s still worth paying attention. According to unnamed officials, the Obama team plans to scrap most of the Kyoto framework for reducing carbon emissions and replace it with a new system of its own devising. Eighty-one days before Copenhagen, we don’t yet know what that system’s going to be–except that it seems to give the US a neat way out of any international agreement by making emission reductions subordinate to domestic laws. Think about it: would you negotiate an arms control treaty that could be scuppered by some pork-barrel filibuster?

Meanwhile Jack Gerard, president of the American Petroleum Institute, has confidently announced that the Waxman-Markey climate bill has no chance of passing the Senate (where, due to health-care wrangling, its introduction has been indefinitely postponed). He’s working hard to make sure he’s proved right: the API is a key organizer of Energy Citizens, a network of oil, coal, trucking and chemical companies attacking the bill with the tactics of the anti-health care lobby.

How much does all this matter? Waxman-Markey is a watered-down compromise which would reduce America’s emissions by a pathetic 1% by 2020–far short of the 25-40% reduction on 1990 levels called for by climate scientists or the 20% reduction agreed by the European Union. The best deal on the table at Copenhagen is widely acknowledged to be less than what’s needed to prevent catastrophic climate change, with only a 50-50 chance of keeping temperature increases below the critical 2 degrees. There are some in the British climate movement who would boycott the whole thing, preferring to expose the pretzel logic of the carbon markets on which any deal will depend and the inflated profits of the firms that trade in them.

And yet it matters–a lot. It matters because climate change is already devastating lives in the global south, and because time is running out for the rest of us as well. It matters because the coincidence of a US president who takes science seriously and a leadership in Beijing alert for the first time to the dangers of warming and flooding is too good a chance to waste. It matters because the recession is a once-in-a-generation chance to push for a sustainable economy and fairer distribution. Climate change is not an environmental issue. It’s about resources and global justice, about the future direction of capitalism, about where the next wars will be.

Copenhagen, on its own, is not going to save the planet. (The planet will make it anyway; it has survived more than one mass extinction in the past.) But as a moment for mobilization, as a lever for shifting the culture, as a global wake-up call, it is unprecedented. Check out some of the organizing that’s going on–on 350.org and climatenetwork.org and the Labor Network for Sustainability and the Deep South Center for Environmental Justice, to name only a few. Don’t leave the argument to the Astroturfers.