The cost of the government bailout of the Wall Street and the US financial system is $2500/person according to libertarian Radney Balko. I agree with his conclusions as well. Wall Street firms took idiotic risks but they were pushed/incentized to do so, at least in some cases.
I have no qualms with criminal and civil prosecution of many Wall Street executives, but it is overly simplistic that they shoulder all the blame. Our government officials and yes even our common citizens who took loans that they couldn’t repay all play a part in this tangled web.
In conclusion, there’s more than enough stupidity to go around.