I think the issue is far greater than a few bad apples, Gilly. I won't pretend to understand all the details, but it's more about making sure that there's credit available for the economy in general to expand. It's not like we can just let a few asshole corporations die out and the good ones will survive, and the rest of the economy will be the better for it. It's more like, no one anywhere can get significant credit and no one can start small businesses or make large purchases (like cars and houses) and even big corporations can't finance their operations effectively. Farmers (the family kind and the factory kind) can't buy the following year's seeds and such. Eventually the fallout hits everybody, there are mass layoffs and senseless shortages and so on. It won't be as bad as the Great Depression because, even through all the deregulation mania from Carter to Bush2, we still have some kind of safety net. But it will still be pretty bad.
Believe me, I hate these corporate fucks more than anyone, but capitalism didn't exist in its current form until there was credit. Once it ceases to become available, the economy starts to contract, and then we're screwed. Again, I don't know how exactly it works, but it's more or less what's happened in the past.