Enforcing Kyoto

Kyoto signatories have a problem: If everyone signed the treaty, they'd all suffer roughly equally -- but if there are holdouts, those holdouts have an automatic incentive to engage in the same high-pollution activities the treaty tries to prevent. France has a solution: Slap a tariff on goods from non-Kyoto countries. Sounds like a good idea, until you realize that it suffers from more or less the same problem: Now, Kyoto signatories who don't go along with France's policy will get cheaper high-polluting imports. The French government may feel righteous, but this mostly makes them poor.