It’s easy to look at the protesters and the politicians in Greece — and at the other European countries with huge debts — and wonder why they don’t get it. They have been enjoying more generous government benefits than they can afford. No mass rally and no bailout fund will change that. Only benefit cuts or tax increases can.

Yet in the back of your mind comes a nagging question: how different, really, is the United States?

The numbers on our federal debt are becoming frighteningly familiar. The debt is projected to equal 140 percent of gross domestic product within two decades. Add in the budget troubles of state governments, and the true shortfall grows even larger. Greece’s debt, by comparison, equals about 115 percent of its G.D.P. today.

The United States will probably not face the same kind of crisis as Greece, for all sorts of reasons. But the basic problem is the same. Both countries have a bigger government than they’re paying for. And politicians, spendthrift as some may be, are not the main source of the problem.

We, the people, are.

We have not figured out the kind of government we want. We’re in favor of Medicare, Social Security, good schools, wide highways, a strong military — and low taxes. Dealing with this disconnect will be the central economic issue of the next decade, in Europe, Japan and this country.