@harpocryptes
Right, a carbon tax fixes the tragedy of the commons inside the jurisdiction that enacts it. That leaves two subproblems:
1. Make it popular to enact it (for democracies). I think a promising option is to redistribute the proceeds of the "tax" equally. Since the median citizen consumes (much) less than the average, most would benefit, precisely the poorer who might suffer the most otherwise.
2. There's still a tragedy of the commons *between* jurisdictions (countries, economic zones) since they share one atmosphere. The rise of nationalism worries me here.