Do market failures create a "durability gap" in the circular economy?

Circular Economy literature recommends longer lasting products, in order to reduce pollution from extraction, production, and disposal. Our economic analysis finds conditions where consumers choose lives that are too short - a "durability gap". Then policies targeting durability raise welfare. While externalities are corrected by Pigovian taxes that ignore durability, raising the output tax nonetheless induces consumers to pay more for goods that last longer. Second, if the tax is suboptimal, a durability mandate raises welfare. Third, internalities have ambiguous effects. Fourth, a social discount rate less than private discount rate is the strongest case for policy to favor durability.