Dow drops nearly 650 points on worries tariffs will slow economy

NEW YORK — U.S. stocks tumbled Monday and wiped out even more of their gains since President Donald Trump's election in November, after he said that tariffs announced earlier on Canada and Mexico would take effect within hours. The S&P 500 dropped 1.8% after Trump said there was "no room left" for negotiations that could lower the tariffs set to begin Tuesday for imports from Canada and Mexico. Trump had already delayed the tariffs once before to allow more time for talks. Trump's...