Kling points out the problem with cap-and-trade carbon limits

From a political economy perspective one important disadvantage of cap-and-trade relative to a carbon tax is that cap-and-trade will develop a long-term constituency. People talk about the irreversibility of the alleged climate change due to CO₂ emissions. If you want to see irreversibility, watch what you happens once companies have a stake in pollution permits. Five years from now, if all the scientific evidence turns out to be that global warming is not an issue, any cap-and-trade program will be all but impossible to unwind.

We can't even unwind our counterproductive ethanol subsidies.

Arnold also makes a case for eliminating macroeconomics. He's on a roll, lately.