A sharp pullback in U.S. hiring for May intensified fears that the economy has weakened and that many employers have grown nervous, in part from President Donald Trump's escalating trade wars. Trump, who has railed against the Fed for not cutting rates this year, may get his wish, if only because his trade conflicts with China, Mexico and other key nations are posing an economic threat. It isn't at all clear how effective Fed rate cuts would be when mortgage rates and other borrowing costs in the United States are already historically low.