By Graciela Chichilnisky The global summit in Copenhagen in December will decide the fate of the Kyoto Protocol, the only international agreement we have ever had to combat the dangers of climate change. But the Protocol expires in 2012 and – like Cinderella – it will become a pumpkin as the clock strikes 12. The Danish capital city is the last stop on the rollercoaster ride of hope and despair since the Protocol was signed by 160 nations in 1997. Partial attempts to move negotiations forward limped from failure to failure in recent years. The world’s two largest emitters – the…