Even worse for flat tax advocates, people don't save much more when the tax on their savings is cut sharply. The positive case for progressivity as the better measure of tax fairness emerges more clearly from the underlying issue of income differences. In theory, flat-taxers are right to criticize a tax system that would penalize people for differences in income that reflect only how hard they choose to work. In real life, income differences reflect much more than effort, if only because people don't start in the same place. At the least, people are born with different talents and grow up in families, neighborhoods and cultures with different resources to prepare them for market competition.
Luck usually plays a part too.
Progressive taxes cannot undo this and shouldn't try. But our commitment to free markets, while disposing the United States to harsher economic inequalities, also can oblige those who benefit so much from them to contribute more as well. The point of progressive taxation is not to penalize those who succeed, but to protect those who have not. As it happens, that's roughly how the current system works. Toting up the combined impact of personal and corporate income taxes, payroll taxes, excise and estate taxes, the data reveal a number of basic and important facts about the current state of tax fairness.