At best, the rising cost of the debt would intensify pressures to increase taxes, cut spending -- or create bigger, unsustainable deficits. By the CBO's estimates, interest on the debt as a share of federal spending will double between 2008 and 2019, to 16 percent. Huge budget deficits could also weaken economic growth by "crowding out" private investment.
At worst, the burgeoning debt could trigger a future financial crisis. The danger is that "we won't be able to sell [Treasury debt] at reasonable interest rates," says economist Rudy Penner, head of the CBO from 1983 to 1987. In today's anxious climate, this hasn't happened. American and foreign investors have favored "safe" U.S. Treasurys. But a glut of bonds, fears of inflation -- or something else -- might one day shatter confidence. Bond prices might fall sharply; interest rates would rise. The consequences could be worldwide because foreigners own half of U.S. Treasury debt.
The Obama budgets flirt with deferred distress, though we can't know what form it might take or when it might occur. Present gain comes with the risk of future pain. As the present economic crisis shows, imprudent policies ultimately backfire, even if the reversal's timing and nature are unpredictable.
The wonder is that these issues have been so ignored. Imagine hypothetically that a President McCain had submitted a budget plan identical to Obama's. There would almost certainly have been a loud outcry: "McCain's Mortgaging Our Future." Obama should be held to no less exacting a standard.