Poor Americans are facing the gravest threat to the federal safety net in decades as President-elect Donald Trump takes office accompanied by a Republican-controlled Congress. The risks to essential benefits for tens of millions of low- and moderate- income Americans include losing coverage extended to them by the Affordable Care Act , threats to the fundamental structure of the Medicaid health-insurance program for the poor, and further reduction of already squeezed funding for scores of other important programs serving the most vulnerable Americans.