This was a market failure, we are told, and the promise of capitalism has always been that the self-correcting mechanisms built into the system would preclude the possibility of a systemic market failure.
But the housing bubble only burst after government subsidies pushed house prices up so fast that marginal buyers could no longer afford to chase prices even higher. A bubble created by rigged financial markets and a government-sponsored obsession with home ownership is not a result of market failure, but rather, a result of bad public policy. The belief that home ownership, per se, is such a benefit that no amount of government support could be too great and no pace at which home prices rise could be too fast is the root of the crisis.
There was no market failure.