Federalism and School Choice

Down on The Corner, Ramesh Ponnuru has written that I seemed a “bit over-hasty” in my recent blog entry stating that federal efforts to promote school choice (outside of Washington, D.C., I should make clear) would be “beyond the feds’ constitutional purview.” Ponnuru suggests that Washington could constitutionally “equalize the tax treatment of payments to private and public schools. That is, stop making state and local taxes (or at least the portion of them that go to public schools) deductible, or start making private-school tuitions deductible.”

I’m afraid I don’t see how either of these fits the dual requirements of being both constitutional and promoting school choice, but I can be pretty dense at times and might need some elaboration.

Concerning the first proposal, I don’t understand how eliminating deductions for state and local taxes would advance choice. The problem is having to pay taxes to support “free” public schools in the first place, not that you can deduct those taxes from your federal taxable income. As far as I can figure, eliminating the deductions would increase the tax burden on public- and private-schooling parents (and all other citizens), but would do little to end the private-schooling penalty of having to pay once for public schools and a second time for private.

With regard to the second proposal, I don’t understand how allowing deductions for private-school tuitions is constitutional. The deductions would be explicitly for schooling, and the enumerated powers for which the Constitution permits Washington “To lay and collect Taxes” include nothing about education.

What have I missed?