President Donald Trump on Friday doubled down on his threat to cut off trade with countries that have surpluses with the U.S. unless the Federal Reserve cuts interest rates. “What I’m saying, very simply, is that we should be paying the lowest interest rate in the world,” Trump said in the Oval Office Friday afternoon. He had been asked about his Truth Social post earlier in the day declaring, “LOWER THE RATE OR I’LL STOP TRADING WITH COUNTRIES WITH WHICH WE HAVE A DEFICIT.” Trump issued that sweeping ultimatum after urging the Fed and its chairman, Kevin Warsh, to “get...