President Barack Obama reflected the consensus view this week when he acknowledged that no agreement on climate change – at least not with specific commitments – would be reached at next month's Copenhagen summit.
Environmentalists and policy makers in many countries are dismayed and discouraged. But now they have an opportunity to fix the problem that has stymied successful co-operation on climate change.
International negotiations to cut emissions of the heat-trapping gases driving climate change are gridlocked in part because of a fundamental misunderstanding about what is fair. The focus has been on greenhouse gas emissions, and on who bears responsibility for cutting them, by how much and when.