[eloff]

Markets suck at pricing on negative externalities. It is literally the textbook example of market failure. That's why we need regulation (e.g. Carbon taxes) to step in and make sure those costs are accounted for.

I don't know what kind of hypothetical utopian market you're referring to, but it's not one that exists in human societies.

[stuaxo]

It's not one that exists yet for sure. It's one we will need to get to, but in the meantime subsidies are most definitely needed.