So while ago I talked about how to scare republicans, and therefore get them to the bargaining table. You have to remember that many Republicans thought patterns are fear based, so getting them to fear what we want is a good way to get them to move in the correct (or "right" if you will pardon the pun) direction.
I had talked about how if we are optimistic, crowing about how much their actions will help Dems win political fights, and restore social spending while gutting the military, they might balk.
But they may think we are wrong about that, so lets talk about their bank accounts (below the fold of course)
So what happens if we default? The issue we need to hammer is this:
The value of the US dollar declines!
If we default, other nations will not want to use US dollars as reserve currency, they won't want to use dollars for the oil exchange (there is already talk of shifting to Euros, this would accelerate that talk). In addition, people all over the world won't hide dollars in their mattresses to hedge against their own currency fluctuations. Folks in China won't seek dollars over Euros or Yen.
Now basic supply and demand tells us that when demand for something, like say the dollar, drops, the price folks are willing to pay for it drops. So as folks all around the world want fewer dollars, our currency will drop in value. World goods will get more expensive, resulting in significant inflation. If you are a rich dude with lots of money in the bank, lots of bonds and CD's, your net worth will fall. If you are a bank, you will get repaid in dollars worth less in goods and services than what those dollars bought when you made a loan.
Even the value of "hard assets:" Stocks in US companies or companies that mostly do business in the US. Real Estate in the US. Capital equipment in the US. All of these will drop in value because they will only produce US dollars, not Yen or Euros or Yuan (Chinese currency).
Heck, the damage to the rich may be greater than the damage to the poor, for while the poor will have to deal with needing a raise to keep paying bills, their debts will drop in real value, while the rich will see all their assets drop.