Canwest News Service: Climate change experts and economists are concerned that Stephane Dion’s failed attempt to sell his Green Shift may leave a lingering stink of failure around the idea of taxing carbon emissions. The concept of a carbon tax is widely seen among experts as Canada’s most efficient and effective weapon against climate change, and surveys taken before the election campaign showed that most Canadians recognized a carbon tax as a “positive step.” But the New Democratic Party and the …