Only days after the 2017 inauguration of Donald Trump, furious Americans gathered at airports across the country in protest of the Muslim ban. But it was the efforts of the American Civil Liberties Union, waging the fight in federal court, that turned the tide, staying the executive order on grounds of unconstitutionality. The ACLU has never granted access to its offices, even as its battles—on the fronts of abortion rights, immigration rights, LGBT rights and voting rights—have become more timely and momentous than ever.