President Donald Trump vowed in his State of the Union speech on Tuesday to build a border wall, which is a source of a deep partisan divide, and said Democratic attempts at “ridiculous partisan investigations” could damage U.S. prosperity. Trump spoke to a joint session of the U.S. Congress facing political discord over his demands that Democrats end their opposition to funding for a U.S.-Mexico border wall he says is needed to stem illegal immigration and smuggled drugs. Trump called illegal immigration “an urgent national crisis,” but stopped short of declaring a border emergency that would allow him to bypass Congress for wall funding.