Guardian: After nearly a decade of George Bush’s denial and obstruction, Barack Obama could hold the key to a new global deal to tackle global warming. Which is why anyone who knows anything about climate change has been waiting for 2009 for a long time. Obama, as they see it, has arrived in the nick of time. The UN negotiations most likely to broker an international treaty have crawled into the home straight and the finishing line is in sight. A deadline of December has been set, …