Earlier this morning, I sat in on a Brookings Institution panel on the upcoming climate talks in Copenhagen, where various countries will try to thrash out a successor treaty to the Kyoto Protocol this December. It sounds like a dry topic, sure, but the panelists actually ended up getting into a heated—angry, even—debate over the role of the United States in these negotiations. The arguments mainly revolved around how much was actually riding on Copenhagen. Does the fate of the planet depend on all 192 or so countries emerging with a robust treaty in hand—or is the situation somewhat less dramatic than that?

On one side, more or less, was Carlos Pascual of Brookings, who argued that, while a global treaty with aggressive targets for emission cuts was absolutely critical to averting drastic climate change, "We can't let the calendar defeat us." It's possible, he argued, that the Copenhagen talks could collapse, or that everyone could agree to a disappointingly weak new emissions regime, or that—as happened with the Clinton administration during the 1990s—the Obama team could leave Copenhagen having agreed to greenhouse-gas reductions that then get rejected by Congress. Indeed, making things especially delicate was the fact that the House and Senate probably won't finish up a domestic cap-and-trade bill before the talks get underway in December. So, he argued, we also need to think about backup plans. (Pascual also pointed out that, thanks to the current financial crisis, it might be difficult merely to achieve harmony among EU member states right now—let alone getting the EU, United States, and developing countries into alignment.)

Two of the European panelists went livid over this suggestion. In their view, Copenhagen really is an all-or-nothing proposition. If the talks go sour, we may have no chance of keeping temperatures from rising more than 2C, which means gambling on the fate of the planet. Yvo de Boer, the executive secretary of the UN Framework Convention on Climate Change, replied that Pascual's view "wasn't good enough—the United States can't come to Copenhagen and mumble." And Connie Hedegaard, the Danish energy minister, argued that setting expectations too low would give the United States and other countries an excuse to go slow—whereas scientists are warning we need to cut emissions sharply as soon as possible. Essentially, de Boer argued that the Obama administration should agree to a robust emissions treaty at Copenhagen and then go home and use that as leverage to push Congress to pass a cap-and-trade bill. (This is similar to what the EU did after Kyoto.)

Pascual replied that politically, it could make it more difficult to pass a climate bill in the United States if Congress feels like it's being forced to meet some target previously agreed on by international diplomats. Rational or not, U.S. senators don't react well to that sort of thing. Pascual suggested that, instead, Congress should pass some sort of resolution agreeing in principle to near-term targets before Copenhagen, in addition to a bunch of other, more modest clean-energy measures, such as a nationwide renewable-energy mandate for utilities. With all that under its belt, the Obama administration could go into the talks with a strong position even if Congress is still bickering over the details of a formal cap-and-trade bill. (And it's very unlikely a cap will get enacted before 2010.)

Anyway, that's all somewhat arcane, but it gives some indication of how difficult it will prove for the Obama administration to negotiate an international treaty and shepherd a cap-and-trade bill through Congress nearly simultaneously, especially since these two things are hardly independent of each other. Timing will be everything.

--Bradford Plumer