Jacob Weisberg has a new Slate article titled The End of Libertarianism: The financial collapse proves that its ideology makes no sense.
It's not a perfect article, and it may claim a bit more than is justified, but the basic point is sound. Financial markets cannot regulate themselves in ways necessary to prevent disasters, contrary to libertarian propaganda.
The largest cause of the financial contagion has been the credit default swap. These are unregulated, high-leverage derivatives that were created to circumvent normal insurance regulations. Without these derivatives, the damage done by the housing bubble collapse would not have paralyzed the entire lending industry.
Libertarians love to claim that markets swirl around and circumvent attempts at government control. Now we see the result of letting them do it. Numerous people called for this to be regulated, but the market fundamentalists were too influential.