President Donald Trump is vowing to spark a manufacturing boom with tariffs to protect American workers and industry. So far, it's manufacturers that have borne the brunt of the pain. The president's surprise decision to raise tariffs on imported steel and aluminum to 50 percent will hit domestic manufacturing just as a new report shows the industry is already contracting. Uncertainty about where tariff rates will ultimately land " or where they'll be applied " has forced businesses to make hard decisions that could cut into both profits and hiring. And a leading trade group on Thursday called on Trump to give the companies a break on the tariffs.