Donald Trump is trying to redefine who is allowed to be a U.S. citizen. On the first day of his presidency, Trump signed an order challenging a long-standing constitutional right that people born inside the U.S. are guaranteed citizenship. The right has been considered settled law since it was ratified as part of the Constitution more than 150 years ago. [time-brightcove not-tgx=”true”] Trump told federal departments to deny the right known as birthright citizenship from children born to mothers and fathers in the country unlawfully.