David Leonhardt gets the story right (mostly). The bankers were acting in their self-interest. They were ripping us off. The one part that is not clear is that we have to cough up the dough to bail out their lenders. I know that the economists who missed the housing bubble and got just about everything else in the last decade wrong tell us that, but it would be interested to see them make their case, rather than just asserting it to be true in the exact same way that they asserted that there was no housing bubble.
--Dean Baker