As China surges ahead with renewable energy (see above), all forward motion seems to have stalled in the US Senate. Two weeks ago, with the November elections in mind and the Republican minority in no mood to compromise, the Senate's Democratic leaders admitted that they would not have the votes this year to pass any kind of cap-and-trade system to curb carbon emissions. Instead, they opted for a scaled-back energy bill that addresses issues such as the Gulf of Mexico oil spill without doing anything to deal with global warming. As Nature went to press, it was unclear whether even that bill would pass. And with the midterm election almost certain to shift a substantial number of seats to the Republicans, who have so far been united in their opposition to what they call 'cap-and-tax', the prospects for more substantive climate legislation next year seem dim.

But behind the scenes, an informal group of energy-industry officials and environmentalists is quietly working on a proposal for compromise legislation that would impose a cap-and-trade regimen on just the electric utility companies — not least because many of the utilities are keen to end years of regulatory and economic doubt. It is unlikely that the group's discussions will bear fruit this year, but lawmakers are paying attention. And it is clear that a solid majority of senators has become convinced that something needs to be done about carbon emissions.

Meanwhile, political pressure for action continues to come from states, communities, environmentalists and many businesses. And everyone on Capitol Hill knows that if Congress fails to move, President Barack Obama's administration will regulate industrial greenhouse-gas emissions using the Environmental Protection Agency's existing authority under the Clean Air Act — a process that is the first choice of no one, including Obama.

Although the political discussion has stalled at the top, there is reason to believe that momentum is gradually building from below — to the extent that at least some Republicans might be more willing to strike a deal next year. They should do so. But if the result is not the comprehensive attack on global warming that many had wished for, perhaps that is inevitable: with an issue as big and complex as climate change, there may be no way to reach consensus on a single piece of legislation that solves every problem for everybody. Instead, policy-makers both in the United States and at the international level will have to keep putting the solutions together one step at a time.