The idea of raising taxes to help society might sound like the ravings of a left-wing radical, or an idea that would destroy American industry. Yet the nation’s leading proponent of a Pigovian gas tax is N. Gregory Mankiw, chairman of President George W. Bush’s Council of Economic Advisers and a consultant to Mitt Romney’s 2012 campaign. Mankiw keeps track of others who support Pigovian taxes, and his unofficial Pigou Club is surely the only group that counts Ralph Nader and Al Gore along with leading conservatives like Charles Krauthammer, Alan Greenspan and Gary Becker as members.
Republican economists, like Mankiw, normally oppose tax increases, but many support Pigovian taxes because, in some sense, we are already paying them. We pay the tax in the form of the overcrowded roads, higher insurance premiums, smog and global warming. Adding an extra fee at the pump simply makes the cost explicit. Pigou’s approach, Mankiw argues, also converts a burden into a benefit. Imposing taxes on income and capital gains, he notes, punishes the work and investment that improve society; taxing negative externalities allows the government to make money while discouraging activity that hurts the overall economy.