Drum goes another round. Avent also replies:

Cap-and-trade can be structured to behave almost exactly like a carbon tax, it has some advantages over a carbon tax, and in basically all the ways that matter it is every bit as good as a carbon tax. It’s the implementation that’s crucial. Those holding out for a carbon tax need to explain why they think Congress would suddenly be less ignorant or craven in debating a tax than they are in debating a cap-and-trade plan, AND they need to explain why the difference in outcome would be large enough to justify the cost of delaying action by a year or several as a new bill was rolled out, sold, defeated a few times, and then eventually passed.

Over to you, Jim Manzi?