Consider the tax on gasoline. Driving your car is associated with various adverse side effects, which economists call externalities. These include traffic congestion, accidents, local pollution and global climate change. If the tax on gasoline were higher, people would alter their behavior to drive less. They would be more likely to take public transportation, use car pools or live closer to work. The incentives they face when deciding how much to drive would more closely match the true social costs and benefits.And this:
Consider the deduction for mortgage interest . . . Subsidies to homeowners are, in effect, penalties on renters — after all, someone has to pick up the tab. But there is nothing wrong with renting. And once one acknowledges that renters are poorer, on average, than homeowners, the mortgage interest deduction becomes even harder to justify.
These are the sorts of places that tax reform might make a significant difference in building a better system. It is true that tax reform in these areas would be politically unpopular. But, in the long run, it might make for a much better and more transparent tax system.