Paul Krugman — who really is becoming the columnist most conservatives fear, judging by some of the silly attacks on him — gives a long but readable overview of what he sees as America's current and looming financial crisis. Here's a key paragraph…
A result of the tax-cut crusade is that there is now a fundamental mismatch between the benefits Americans expect to receive from the government and the revenues government collect. This mismatch is already having profound effects at the state and local levels: teachers and policemen are being laid off and children are being denied health insurance. The federal government can mask its problems for a while, by running huge budget deficits, but it, too, will eventually have to decide whether to cut services or raise taxes. And we are not talking about minor policy adjustments. If taxes stay as low as they are now, government as we know it cannot be maintained. In particular, Social Security will have to become far less generous; Medicare will no longer be able to guarantee comprehensive medical care to older Americans; Medicaid will no longer provide basic medical care to the poor.
What makes me think he's probably (unfortunately) correct is that while his detractors will fault certain perhaps-arguable calculations, they kind of skip over or ignore this kind of pronouncement. They don't rebut him by arguing either that cutbacks in the safety net will not happen or even that they're a good thing. Anyway, read the whole piece and decide for yourself.