The revolving door between the big banks and the Federal Reserve isn't just unseemly — it's a time bomb. Here's how to fix it. Fed Governor Jerome Powell also worked in finance, if not banking. He spent his career in private equity, an industry that uses debt financing to buy, restructure, and then sell firms. Powell worked at Carlyle Group, where he amassed the largest personal fortune of any current Fed official, amounting to tens of millions of dollars. It’s not that bankers and other financiers are not qualified to be central bankers. An understanding of finance is important to...