Earlier today, I spoke with Glenn Hubbard, dean of Columbia University’s Graduate School of Business and former chief economist to George W. Bush. He’s not happy to see Congress dithering over the debt ceiling, and he had a nice analogy for why. “It’s not useful for me and my wife to argue over whether we’re going to pay our bills,” he told me. “What’s useful for us is to discuss whether we should work more or spend less. But not whether we’ll pay.” And that’s what the debt ceiling is about: not how we’ll pay our bills but whether we’ll pay the bills we’ve already racked up.