Are low interest rates doing more harm than good?

Mark Carney was oddly framed by TV cameras when he made his hasty post-Brexit address the morning after the United Kingdom voted to leave the European Union. Standing behind a lectern, but in front of an open doorway, the governor of the Bank of England appeared as though trapped inside a box. It was fitting for a man who’s now expected to fix the U.K.’s looming economic crisis using, mainly, a single, indiscriminate weapon—interest rate policy—that’s been mostly emptied of ammunition. Nevertheless, as the British pound plunged to a 31-year low and stock markets around the world temporarily swooned, Carney declared...