"Joseph Stiglitz, with two colleagues, the Orszag brothers (Peter and Jonathan), looked at the very same Fannie Mae. They assessed, in a report, that "on the basis of historical experience, the risk to the government from a potential default on GSE debt is effectively zero."* Supposedly, they ran simulations--but didn't see the obvious. They also said that the probability of a default was found to be "so small that it is difficult to detect." It is statements like these and, to me, only statements like these (intellectual hubris and the illusion of understanding of rare events) that caused the buildup of these exposures to rare events in the economy. This is the Black Swan problem that I was fighting. This is Fukushima."