7. Without a doubt, a global solution is imperative
Im just highly skeptical that making dirty energy more expensive will lead to a drastic (as that is what is needed) reduction in atmospheric carbon.
Another problem is that green infrastructure requires dirty energy to create. Making this energy more expensive makes building windmills and solar panels more expensive as well, thereby pushing further back their timelines to becoming carbon neutral.
A carbon tax is a market based solution essentially. You fidget with the numbers and hope everything works out for the best.