Wall Street's main indexes were mixed on Monday after President Donald Trump said he plans to double tariffs on imported steel and aluminum, fueling more uncertainty around U.S. trade policies. Trump said late on Friday he planned to increase tariffs on imported steel and aluminum to 50% from 25% starting Wednesday,

Wall Street has a new shorthand about President Donald Trump — and he’s not happy about it. Traders have reportedly come up with the acronym TACO, which stands for “Trump always chickens out,” to describe the tumultuous trade environment created by the president’s habit of threatening to impose tariffs on countries,