There's a right way and a wrong way to criticize Paul Ryan's Roadmap, and the Washington Post's Matt Miller is doing it right. Here's his problem with Ryan's tax policy, which targets federal tax revenues at 19 percent of GDP:

How can we double the number of Americans on Social Security and Medicare as baby boomers retire and keep taxes at the same level they were when America's population was much younger? Why isn't an increase in taxes as a share of GDP unavoidable as we accommodate an aging population -- making the real question how to finance the boomers' retirement via a reformed tax system that does the least harm to growth? Unless your answer is that we can double the number of seniors who are covered by halving their benefits, your 19 percent assumption can't possibly add up.

Cosign. One thing I wish he mentioned was Ryan's focus on means-testing expensive programs like Social Security and Medicare, which strikes me as inevitable.

Three things have happened simultaneously in the last few decades: the concentration of money in the hands of the top decimals has ballooned, middle-class wages have stagnated, and we've promised trillions in tax-funded benefits to both. It seems to me that an initial, uncontroversial approach to this problem should be to preserve the guarantees for the middle class by rolling back the guarantees for the top percentile crowd.

This isn't a Trojan Horse designed to punish the upper-middle/lower-upper class. I'm not talking about cutting Social Security and nursing aid assistance for families in the $100K range. It's an acknowledgment that our promises cost more than our taxes, and the most pain-free way to bring those in line is to start shaving bennies at the zenith. I don't like Paul Ryan's million-dollar tax cuts at the top percentile, but I agree with him that so long as the millionaires have all those millions, we shouldn't treat them to the same government benefits.

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