When one encounters the statement above, it is typically in reference to what it might cost in terms of lost output from now going forward should policy be enacted to reduce CO2 emissions. That is in some sense a very easy analysis to do. What is far more difficult to do is estimate what the current costs of global warming policy are. How much intellectual energy is being directed into studying global warming? How much lobbying and rent-seeking is done to secure particular policy outcomes related to global warming? How much are energy costs higher today because of the prospects of future global warming policy? How much economic activity is being diverted to unproductive green elephant energy products? How much education about more important environmental problems (coastal eutrophication for example) is being tossed aside because of a focus on policy? And how much optimism, ambition and hope is being instilled in our children when they are regularly told that humans are nothing better than a malignant cancer and that we’ve already doomed countless species to extinction and even threaten our own existence because of our evil capitalistic ways? Do I really want my 6 year old learning how to write letters to their elected official? Or do I want my 6 year old to get some gumption and learn how to take some risks and be inventive and entrepreneurial? I understand those are not mutually exclusive of course.
So, if I were a real economist, I’d spend a few weeks doing these estimates. Kudos to anyone who wishes to take a crack.