According to the article below (from Associated Press), regulators in the Bush Administration should have been more vigilant regarding the rules for subprime lenders, but were pressured by lobbyists; as a result, we have the current mortgage fiasco.
I'm sure that's likely, but let's consider another possibility as well. In my opinion, the relaxation of lending rules (which began with Bill Clinton's Administration) was brought about precisely in the hopes of creating a fiasco...so that the Fed Govt could launch a massive intrusion into the marketplace and expand its activities in the private sector. Which has happened. Can I prove that the goal was to create a fiasco? Of course not; it's just an opinion...a possibility. Basically, it's just a hunch. But it does fit right in with the tendency of NeoCons in government to expand the reach of government, and with their proclivity to utilize Machiavellian methods.
Google "Neo-Conned", by Ron Paul.