Let’s tax plastics first

One step at a time.  Start with plastics, tax other carbon later.

Plastic’s enormous negative externalities are more localized than burnt carbon’s.  A nation or a state could readily tax plastic, unlike all carbon.   A simple weight tax would be an easy, easy place to start.  Refinements, if any, could come later.

AND a tax on plastics would largely avoid the trickiest part of carbon tax design — the task of creating a Border Trade Adjustment.  A BTA would be essential for a carbon tax, to keep foreign manufacturers from beating tax-paying domestic competitors.  A carbon BTA would be the work of many lifetimes.

But a tax on plastics can simply omit a BTA.  Plastics used in manufacturing are trivial, so domestic producers need not fear imports beating the system.  It would cost more to figure the tax than it would yield.  You could tax manufacturers and first importers by the gram or pound.  You could start with single-use plastics.  This is even more obviously needing to happen than taxing even weed.