The government says cap and trade dropped acid rain emissions 50% in the Northeast. However, dealing with GHGs worldwide is way more complicated than reducing one pollutant gas in one area. Especially when polluters could and did simply move polluting plants from the Northeast to elsewhere. Also, low-sulfur coal became economical at the same time. So, the reduction wasn’t really caused by cap and trade at all.
Green Thoughts has a long, thoughtful explanation of why cap and trade can’t and won’t work.
Cap and trade in its scientific attitude, orientation to politics, financial market design, and permit regulation all have one commonality: the cap and trade system inserts one or more extraneous elements that do not serve the purpose of cutting emissions or increasing the overall efficiency of the system. In most cases this “stop” along the way to achieving the goal is some form of “visit” to the carbon market before the actual job of cutting emissions or financing the emissions cutting projects can occur.
That will allow the vampire squid to extract profits, game the system, while pretending to care about the environment.
The insertion of the carbon market into the process impedes rather than enhances the process of cutting emissions as this inserts variability and the structure of the permit market and its many superfluous stakeholders into the emissions cutting process.
All of which will do little or nothing to reduce greenhouse gases.