First off, the entire economy wouldn't have failed in a decade.Stop being a douche.
A total lose in paper money is far greater than most forms of inflation (minus hyper-inflation see: Germany after WW1, which is just slightly better). Of course it's going to affect the world economy, no one is debating that anywhere. The debate stems from which is worse: letting the US economy completely fail within a decade, or bailing out/nationalizing organizations and try to turn the situation around. Of course neither case is optimal, but this is where America is now.
And it is that way now because of unregulated, unethical, capitalistic free markets.
The debates in this thread vary all over the place. 100% capitalism is a theory that doesn't exist in reality, just like 100% socialism is. Neither can exist in a world filled with people who will act like people. Therefore, trying to position an economy too far to one side of a theoretical, impossible model is doomed for failure. Completely free market capitalism doesn't, nor can it ever, exist. And if you try to make it exist, you'll just shoot yourself in the foot over and over again.
Secondly, they have traded potential short term "relief" for long term devaluing of the dollar, inflation, and by dumping our debt onto the next generation. I don't think that is a wise compromise.
Third, "and it is that way now because of unregulated, unethical, capitalistic free markets" is complete bullshit. We do not have "unregulated free markets", we have poorly regulated "semi-free-ish in some industries markets". And bailing them out when they fuck up doesn't really set any good precedents for people to make responsible business decisions, does it?