JUST TAX CONSUMPTION:

Many Americans may find this hard to believe, but the United States already has one of the most progressive tax systems in the developed world, according to several studies, raising proportionately more revenue from the wealthy than other advanced countries do. Taxes on American households do more to redistribute resources and reduce inequality than the tax codes of most other rich nations.

But taxation provides only half the picture of public finance. Despite the progressivity of our taxes, according to a study of public finances across the industrial countries in the Organization for Economic Cooperation and Development, we also have one of the least effective governments at combating income inequality. There is one main reason: our tax code does not raise enough money.

This paradox underscores two crucial lessons we could learn from the experience of our peers around the globe. The first is that the government's success at combating income inequality is determined less by the progressivity of either the tax code or the benefits than by the amount of tax revenue that the government can spend on programs that benefit the middle class and the poor.

The second is that very progressive tax codes are not very effective at raising money. The corollary -- suggested by Peter Lindert of the University of California, Davis in his 2004 book "Growing Public" -- is that insisting on highly progressive taxes that draw most revenue from the rich may result in more inequality than if we relied on a flatter, more "regressive" tax schedule to raise money from everybody and pay for a government that could help every American family attain a decent standard of living.

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