Calculating harm is difficult (what price do you put on a refugee displaced from some now-unlivable region?), but one could instead calculate the cost of removi

Calculating harm is difficult (what price do you put on a refugee displaced from some now-unlivable region?), but one could instead calculate the cost of removing that CO2 from the atmosphere by whatever is currently the most economical means (aside from natural processes that happen without human intervention). Realistically, though, it's more likely that the value of any carbon tax will not be calculated by some formula, but rather by what a handful of democratically-elected leaders deem is reasonable. Which might not be completely satisfying from a fairness point of view, but I think it's greatly preferable to not having a carbon tax at all (which is equivalent to saying, "quantifying harm is hard to determine, so we'll just pretend it's zero").