> or it will get raised too high and be used to do something unrelated That matters very little. Carbon taxation is a Pigovian tax, and just making emitting CO

> or it will get raised too high and be used to do something unrelated That matters very little. Carbon taxation is a Pigovian tax, and just making emitting CO2 more expensive creates strong incentives to stop emitting CO2. It also makes "green" alternatives comparatively cheaper. In fact, many proponents of carbon taxation support equal redistribution of the tax money to everyone (e.g. as tax credits). Taxpayers polluting less than average would see their tax burden decrease, while those polluting more than average would be paying more and thus be incentivized to change their behavior. (Of course, it's not that easy in the real world, some behavior can be extremely hard to change without help/subventions/large investments. But these helps don't have to be tied to carbon taxation.)