A few years ago, Noam Chomsky did an interview with The Real News Network where he talked about systemic risk. The important point is that certain types of risk are underpriced. Chomsky says in part that financial institutions:

"calculate the potential cost to themselves if there's a loss. The important words are "to themselves." They don't calculate in what's callaed "systemic risk," the effect on the whole system if I go bust. And it has a huge effect. The result is that risk-taking is underpriced, meaning there's a lot more of it than there would be in a reasonable system."

This begs the question why systemic risk isn't talked about more in our normal political discourse. You can find plenty of discussion in the academic literature, but it's an issue that's considered too arcane for mainstream politics. This is frustrating, because it's a big issue and one that isn't all that difficult to explain (Chomsky does a good job). Assuming people can't comprehend something and talking about, say, Anthony Weiner instead just leads to bad long-term policy. 

Recently, Daniel Tarullo, the Fed Governor responsible for regulation, said that the "regulatory structure for SIFIs [systemically important financial institutions] should discourage systemically consequential growth or mergers unless the benefits to societyare clearly significant." Capital requirements for banks are likely going to be increased in the U.S., and mergers are being de-incentivized. This basically means that too-big-to-fail banks are going to be discouraged from getting any bigger This is encouraging stuff-- and a recognition that the platform of deregulation faces some serious problems. Let's hope they go far enough.