Guardian: The US backtracked yesterday on the climate change agreement reached after marathon talks in Bali, saying it had "serious concerns" about the new global consensus and that developing countries had to do far more if there was to be any pact in two years’ time. The reality check followed the drama and euphoria of the weekend when the US was shamed into joining the rest of the world in working towards a new climate change agreement to come into force after 2012. All 190 …