i would support a north american air pollution taxation scheme, where polluters on both sides of the border (including gasoline consumers) are taxed to compensate for the externalities resulting from the pollution they generate, including health care costs. an integrated, international carbon tax would address some of the criticisms in the way that more localized carbon taxes essentially offshore pollution. that's a good idea, and i hope the governments of canada and the united states sit down and work out a serious implementation.