US debt default will do that? How?
Although I don't think the US will default on its debt just because it can't borrow more. In fact, every dollar paid in Social Security reduces the debt. The US is free to issue bonds up to the limit. This, like the rush to appropriate money for all those "shovel ready" jobs that didn't exist, is just another money grab.
There are debts this country has run up..like financing 2 wars..that we will default on. If there isn't enough money in the treasury to finance those debts..penalties will accrue. We also have foreign debts subject to the same risk.
What this will do is demostrate to other nations that this country is so dysfunctional it cannot even take care of it's finances. They will look to other currencies to purchase and peg their own to. And they will look to other countries to make trade agreements with.
This works fine if your goal is to be a pariah and isolationist. And it would turn this country, effectively, into a third world country with a big military.
How's that working out for the Democratic Republic of North Korea?