The latest development in the Libor-manipulation scandal is that the banks weren’t really fixing the price of the key interest rate in total secret — US regulators were aware of the sleazy activities at the time, and seemed to have done nothing. Which should surprise no one. I can’t tell you how much federal officials knew about the activities of Barclay’s, JPMorgan, Citigroup and the other big banks at the center of the maelstrom. In coming weeks, both Federal Reserve chief Ben Bernanke and Treasury Secretary Tim Geithner will inevitably discuss the mess when they appear before Congress. Bernanke testifies...