[...]In the first place, our debt payments do not simply go to enrich feckless corporations. They go into things like insurance pools, 401(k)s, and pension funds. If the government stops payments, yes, some rich people would take a bath. But so would a lot of ordinary people.
Even more importantly, if the government misses a debt payment, that's it for borrowing more money in the near future--and I, for one, am skeptical that the IMF would be able to mount a bailout, which is what we do when developing nations have this sort of trouble. The United States currently runs a $1.5 trillion budget deficit. If we miss a debt payment, that means we immediately have to balance that budget, and keep it balanced. You have probably seen a lot of blog posts lamenting the terrible plight of the states, who cannot run budget deficits during recessions and are therefore forced to make draconian cuts to services unless they are bailed out by the Feds. Well, if we can't borrow money, no one's going to bail us out--or the states. And you can expect a default to be followed by a pretty ugly recession in an economy as credit-driven as ours.
That said, obviously the best thing to do is raise the debt ceiling, and not put the US government at risk of default. But second best is to buy time while preserving our credit rating. Over the long run, if the credit taps get cut off, the social service cuts will be deeper, uglier, and permanent.
States can't print money. The federal government can. What is going on here? Several commenters noticed this too but their protests were drowned out in the general din.