TAX WHAT YOU DON'T WANT, NOT WHAT YOU DO:

According to the Roberts opinion, the healthcare mandate is really a tax incurred when an individual fails to purchase health insurance. While legal scholars tussle over whether taxing inactivity is a new doctrine, taxpayers are already facing such impositions with every break in the code they don't take advantage of.

Consider the home mortgage tax deduction: Everyone who doesn't own a home is paying more taxes than they otherwise would to subsidize all the homeowners enjoying their break. The same goes for the "charitable" deductions, by which we all pay more than we otherwise would to cover everything from the country's churches to its super PACs, and the child tax credit, effectively a tax on those of us without progeny. Every deduction that you don't take advantage of is essentially a tax on your inactivity. We don't complain about that because many, though not all - I'm looking at you, mortgage deduction - of those tax breaks serve a social function we value.

Taxes are often used as a vehicle to encourage or discourage various kinds of behaviors, and tax reformers - including the next president, whoever he is - should learn from healthcare's lessons about what kind of incentives to adopt. In the case of the healthcare tax/mandate, the idea is that getting everyone health insurance is going to save us all money in the long run, same as giving parents a tax break and subsiding civil society do-gooders. All of this contributes to a happy, growing society.

The key policy distinction between healthcare and home mortgage tax breaks, however, is that there is evidence that purchasing health insurance benefits the public - which no longer has to subsidize your emergency room visits - while subsidies for housing seem to have far fewer (and indeed many worse) consequences. If tax reform is discussed next year, it will be about controlling wild corporate lobbying and messy deals, but it will also be about how Congress can maximize the good tax breaks while eliminating the bad ones.

Economists tell us that the best tax regimes penalize negative actions - like not having healthcare insurance or buying cigarettes - while keeping the burden light on positive actions, like earning income or purchasing necessities. The healthcare tax isn't quite a traditional consumption tax, but it comes from a similar impulse to tax bad things rather than good ones. As Mankiw puts it in a manifesto favoring these taxes [PDF], "individuals can be charged for the external costs they impose on others." It could be an argument for the Obamacare mandate.

These kinds of taxes aren't necessarily politically popular; they often target both entrenched interests and the populace at large. The best-known examples are the gas tax, which exists, and the carbon tax, a broader tax on fossil fuels that, in the U.S. at least, is but a flicker in the imagination of policy wonks. The Democrats' aborted effort to create a cap-and-trade system to fight air pollution in 2009 was essentially a roundabout way of implementing a tax on pollution, but it failed in a gridlocked Congress, while facing intense opposition from the energy industry.

But in the future, consumption taxes are likely to be more popular than either jacked-up income tax rates or massive cuts to social spending. 

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