Copenhagen was a disaster. That much is agreed. But the truth about what actually happened is in danger of being lost amid the spin and inevitable mutual recriminations. The truth is this: China wrecked the talks, intentionally humiliated Barack Obama, and insisted on an awful “deal” so western leaders would walk away carrying the blame. How do I know this? Because I was in the room and saw it happen.

China’s strategy was simple: block the open negotiations for two weeks, and then ensure that the closed-door deal made it look as if the west had failed the world’s poor once again.

I saw Obama fighting desperately to salvage a deal, and the Chinese delegate saying “no”, over and over again.