I'm never quite sure what the answer is to questions like this. The capitalist ideal says, let 'em go hang. They made their bed and they should be prepared to lie in it. The trouble is that by letting them tumble you're hurting the general public. So you have to bail them out for the good of the public. But once you've gone down that route you remove any impetus from large companies to trade responsibly and take a long term view. I don't know enough to comment on the US Auto industry or the banking industry but I'm damn sure that attitude in the UK banking industry has been a large part of the reason we're in this mess in the first place (and I get the impression from the media that the same is true of the US banking industry).

So how do you hold companies to account that have become so large that their collapse will hurt the public? The only suggestion I can make is nationalisation on the basis that if we're paying for it we might as well own it. While that might be suitable for some industries, though, banking is definitely not amongst them.