With respect to the GSE leg of the problem, this was W’s call for reform in 2003 (after Clinton had also warned of problems), from the NYT:
New Agency Proposed to Oversee Freddie Mac and Fannie Mae
By STEPHEN LABATON
Published: September 11, 2003
The Bush administration today recommended the most significant regulatory overhaul in the housing finance industry since the savings and loan crisis a decade ago.
Under the plan, disclosed at a Congressional hearing today, a new agency would be created within the Treasury Department to assume supervision of Fannie Mae and Freddie Mac, the government-sponsored companies that are the two largest players in the mortgage lending industry.
The new agency would have the authority, which now rests with Congress, to set one of the two capital-reserve requirements for the companies. It would exercise authority over any new lines of business. And it would determine whether the two are adequately managing the risks of their ballooning portfolios.