Taxing carbon

Would it impact gasoline consumption? Kevin Drum doesn't think so and neither do I. The numbers just arent there. Here's Kevin:

None of this is to say that a carbon tax isn't a good idea. It is, and probably at levels higher than... $25 per ton. But the hard fact is that it would have only a modest effect on gasoline usage. If we're serious about cutting back, we need other, better policy instruments, like low-carbon fuel standards (Sperling's suggestion), higher CAFE standards, refundable gas guzzler taxes, and so forth. Carbon taxes are only a start.

He's absolutely right. Which is why all serious climate change proposals--carbon tax, cap and trade, or both--are paired with complementary policies like those.