Where they've been tried, the evidence shows, well-designed carbon taxes have succeeded in reducing greenhouse-gas emissions. But that doesn't necessarily end the debate over their effects -- nor should it. The next question is whether that success is bought at the expense of jobs and incomes.
The answer is no. As long as the tax is well-designed, it can cut emissions at little or no economic cost. And that is a conservative assessment: In practice, a carbon tax has been shown to provide an economic boost. The reason is that the revenue raised by a carbon tax can be used to cut other, more damaging, taxes.