Despite John McCain's reputation for straight talk, we're not hearing much from him on tax policy. Then again, Barack Obama has not been much better. Both senators are proposing tax plans that would dig the federal budget hole trillions of dollars deeper.

An analysis of the candidates' plans by the Tax Policy Center, a joint project of the Urban Institute and the Brookings Institution, concluded that McCain's tax ideas would crank up the national debt by $5 trillion over the next decade. Obama's plans would increase the debt by $3.4 trillion. The campaigns complain the center doesn't factor in their plans for budget cutting, but we're skeptical McCain and Obama could cut enough to make up the yawning gaps in their accounting.

Besides that, neither candidate is proposing substantive solutions for reforming Medicare and Social Security, the cost of which is about to balloon and put severe stress on government finances. McCain and Obama know as well as anybody that the government cannot keep the promises it has made to voters and that the bill is coming due.

Even so, the same moldering rhetoric spills from them — McCain paints Obama as a tax-and-spend liberal. Obama tars McCain with the Bush brush. Little of substance is proposed.

The TPC analysis found that McCain would reduce taxes an average of about 3 percent of income for middle-income earners, or about $1,400 annually, by 2012 but would give the top 1 percent of earners a much larger break, cutting their taxes by $127,000. He would extend the Bush tax cuts and reduce corporate taxes, both questionable ideas. Other elements of his plan make more sense, including making permanent the research and development tax credit.

Obama would reduce taxes for low- and moderate-income families but would raise them significantly on the rich. OK. But his thinking clouds when it comes to tax breaks, including questionable proposals for new breaks for retirees and homeowners. And his plan to boost taxes on capital gains and dividends discourages investing and hurts those who rely on such income streams.

The nation faces a fiscal crisis in the coming years. Social Security and Medicare are unsustainable without changes. Tax hikes or cuts in benefits or — better — a combination of those cures is needed. The nation must not try to borrow its way out of this problem by running up crushing deficits that crowd out private investment and weigh down the economy.

Sens. McCain and Obama: Run these plans through the spreadsheet again. And then level with the voters.

REPRINTED FROM THE MILWAUKEE JOURNAL SENTINEL.