Watch as former Prime Minister Stephen Harper comments on a carbon tax. A carbon tax is not an environmental policy. People who want carbon taxes want money for the government. A carbon tax is a revenue policy, a way for generating more revenue for the current government, which cannot raise the GST. A carbon tax would have to be astronomically high to have any profound effect on fuels and emissions but it does provide a steady stream of revenue and those that want it know this. It is just another way of raising taxes. Some politicians in Canada know this and are opposing it for that very reason.