economist: The game is up

During two exceedingly prosperous decades, that theory seemed to work just fine. But the swings in almost all financial markets this month have made dispersed risk suddenly morph into dispersed mistrust. The uncertainty has been magnified by the way that bad risks have become so hard to value. Investors have bought asset-backed securities that use shaky subprime mortgages in America as collateral, but as defaults have risen, the value of that collateral has tumbled.