Debt Ceiling

Consider a person who is well to do and has good credit. He decides to semi-retire for 10 years and then buys two fast cars. The cars keep breaking down and he's not earning enough. So he borrows money to make up for it. Folks are happy to lend him because he has good prospects and he has always paid back the money he owes. Then he signs a magnanimous contract to pay regularly to a charity even though he doesn't have the money. But folks are again happy to lend him cos' he always pays back with interest. Suddenly, his accountants skip town with a lot of his cash and folks begin to question his prospects. But he still continues to pay the interest on his loans. He needs to have good credit because he's not making as much as he's spending and he needs to continue to borrow to keep things running. He tries to revive his prospects with advertising. This costs more money but he shortchanges on the advertising and his prospects continue to be bleak. But he continues to pay interest on his loans.

Then, he decides cold that he just won't borrow anymore even though he knows he doesn't have enough to pay for what he has borrowed already and his prospects for income are still bleak. He's gonna have to get out of semi-retirement, dump his cars and re-negotiate with that charity. But he'd rather cut down on his essentials than give up on those things. And if that isn't enough to pay folks back, he'll just default on his loans. His lenders are livid and stop lending him money and his credit rating tanks.

This is as close an analogy as I can conjure to explain the debt ceiling fight going on in Congress.

Update:
Apologies to Felix Salmon for the metaphor.