Guardian: Barack Obama, who promised last week to write a “new chapter in America’s leadership” on the environment, could find his hands tied by the economic crisis, a leading figure in global climate change negotiations said yesterday. John Kerry, who will lead the US Senate’s delegation to the UN’s climate meeting in Poznan, Poland, next month, said his country was now in a position to play a leading role on global climate change negotiations. But he also said Obama’s administration would be …