The Pope on Cap-and-Trade

At my school, people care a lot about what the Pope thinks, and it appears that the Pope does not think much of cap-and-trade policies for reducing carbon emissions. From his encyclical:

171. The strategy of buying and selling “carbon credits” can lead to a new form of speculation which would not help reduce the emission of polluting gases worldwide. This system seems to provide a quick and easy solution under the guise of a certain commitment to the environment, but in no way does it allow for the radical change which present circumstances require. Rather, it may simply become a ploy which permits maintaining the excessive consumption of some countries and sectors.

Perhaps by "carbon credits" he means carbon offsets, which indeed have been misused... but this is a question of implementation, not principle. But it seems by "carbon credits" he may intend "cap-and-trade." If so: Bad call, Frank... Cap-and-trade is not a panacea, but it is a powerful policy tool. You should have an audience with Bob Stavins... he cares a lot about this stuff, and he knows a lot more about policy than you do...

“I respect what the pope says about the need for action, but this is out of step with the thinking and the work of informed policy analysts around the world, who recognize that we can do more, faster, and better with the use of market-based policy instruments — carbon taxes and/or cap-and-trade systems,” Robert N. Stavins, the director of the environmental economics program at Harvard, said in an email.