Donald Trump began his Presidential bid, in 2015, with an infamous speech, at Trump Tower, in which he said of Mexican immigrants, “They’re bringing drugs. They’re bringing crime. They’re rapists.” But it was not until a former aide to Jeff Sessions joined Trump’s campaign that the nativist rhetoric coalesced into a policy platform—including the separation of children from their families at the border. Jonathan Blitzer, who writes about immigration for The New Yorker, has been reporting on Stephen Miller’s sway in the Trump Administration and his remarkable success in advancing an extremist agenda. “There has never been an American President who built his campaign around the issue of immigration and later won on that campaign on immigration. Trump was the first and only President really ever to do it,” Blitzer tells David Remnick. Despite this influence, Miller remains largely behind the scenes. Blitzer explains why: “He knows that the kiss of death in this Administration is to be identified as the brains behind the man. He can’t let on that he’s the one who effectively is manipulating Trump on these issues.”