Krugman, Paul, “Now and Later,” The New York Times, 06/20/10

At the moment, as you may have noticed, the U.S. government is running a large budget deficit. Much of this deficit, however, is the result of the ongoing economic crisis, which has depressed revenues and required extraordinary expenditures to rescue the financial system. As the crisis abates, things will improve. The Congressional Budget Office, in its analysis of President Obama’s budget proposals, predicts that economic recovery will reduce the annual budget deficit from about 10 percent of G.D.P. this year to about 4 percent of G.D.P. in 2014.
Unfortunately, that’s not enough. Even if the government’s annual borrowing were to stabilize at 4 percent of G.D.P., its total debt would continue to grow faster than its revenues. Furthermore, the budget office predicts that after bottoming out in 2014, the deficit will start rising again, largely because of rising health care costs.
So America has a long-run budget problem. Dealing with this problem will require, first and foremost, a real effort to bring health costs under control — without that, nothing will work. It will also require finding additional revenues and/or spending cuts. As an economic matter, this shouldn’t be hard — in particular, a modest value-added tax, say at a 5 percent rate, would go a long way toward closing the gap, while leaving overall U.S. taxes among the lowest in the advanced world.
But if we need to raise taxes and cut spending eventually, shouldn’t we start now? No, we shouldn’t.