Not to mention that if our economy, or currency, goes completely under, no one is going to bail us out. Maybe halfway.
Maybe they'll drop food for us.
The world economy is so tied to ours that if we go, most of the world goes. And when that happens, it will be open season for regime changes, border wars and ethnic cleanses across the globe. Ain't nobody dropping food for us, they'll be desperate to hang on to what they have.
We're actually in a pretty strong position if we get back down to brass tacks. We have natural resources, food and fuel in our own country. Even after a breakup, we can trade with neighboring states without ever worrying about trade outside north america.