I think Lomborg's got a good argument in favor of a conclusion he leaves unstated (and may, in fact, not favor) - that some portion of the money governments wou

I think Lomborg's got a good argument in favor of a conclusion he leaves unstated (and may, in fact, not favor) - that some portion of the money governments would spend on sustainability should instead be spent on finding a proactive solution to climate change, e.g. extracting large quantities of carbon from the atmosphere. Doing nothing and hoping someone independently solves the problem strikes me as an unacceptable risk; there is little market incentive at the moment to reduce environmental damage. A carbon-trading scheme would create such an incentive, but would no doubt create its own inefficiencies. Markets are great at dealing with resource shortages, for example whale oil, but quite bad at dealing with negative externalities, e.g. air pollution. It took government intervention to clean up London (I think? I don't have any sources on this). Spending money on proactive solutions encourages economic growth instead of discouraging it, and can lead to future benefits as "green technology" leads to new advances. On the other hand, it's somewhat risky as most avenues of inquiry will lead to dead ends, and any geo-engineering technology that becomes widely adopted could have nasty side-effects.