The cause of the crisis was extreme levels of moral hazard within the entire financial industry, which was allowed to proliferate by sloppy and inadequate legislation by a set of governments firmly in the thrawl/pocket of the industry.
The financial markets are so far away from the capitalist model of perfect competition its untrue. We don't need more or less regulation per se, we just need better legislation aimed at creating a more transparent banking process. Completely destroying the whole liquidity system is not the answer. You don't fix a car by removing all the oil.
That in combination with an incomplete housing market was the main problem. This needs addressing as well.