The music stopped as the investment giant Lehman Brothers filed for bankruptcy 10 years ago Sept. 15. It was a tipping point in the sequence of events that soon became known as the global financial crisis. The event upended American economic complacency and set in motion a wave of populist animus against finance. While the crisis was arrested—albeit in a way that would sow future problems—the populist flames burn away.
Should the U.S. government have saved Lehman? Prices of Lehman debt before the bankruptcy indicated some...