Toronto Star: After hours of chaotic, sometimes angry haggling, the United Nations conference on climate change last night appeared set to approve what critics describe as a weak deal on cutting greenhouse gas emissions. Nerves were frayed as sleep-deprived delegates from nearly 190 countries repeatedly edged to the brink of agreement, then pulled back into more acrimonious debate. Each move further diluted a compromise that, from the outset, was, “a lot of structure with not a lot of …