Now there's a big "IF." A carbon tax would raise the price of every good and service from airliners to ball point pens. The idea of such a tax producing "unexpected benefits" is the triumph of delusion over reality. The very idea that the Chinese would emulate a lemming-like leap into the sea of recession is laughable.
What makes the whole thing even more risible is that the net human addition of CO2 to the atmosphere is infinitesimal in terms of a percentage of the atmosphere at large. This governmental blunder would be a solution in search of a problem, like Carter's wasted "Synfuels" fiasco.
But because CO2 is an active absorber of longwave radiation, small changes in its concentration have significant effects. There is very little ozone by weight in the stratosphere, but what is there is very important for the absorption of solar UV.