During the height of Roy Cohn’s friendship with Donald Trump, according to the historian Kai Bird, “they were on the phone with each other a dozen times a day.” Bird’s new book, “American Scoundrel,” details Cohn’s profound influence on Trump—whom he met as a young real-estate heir in the nineteen-seventies—and how Cohn is “haunting” politics in our time. “I had written about Roy Cohn in [previous biographies] as this nefarious, minor, awful figure who was disruptive and divisive and unethical. And I suddenly realized that the establishment that I’d been writing about for forty years is gone. Their values and culture, the politics, the bipartisanship . . . that’s all gone,” he tells David Remnick. “Roy Cohn explains something about the dark side of America that I just didn’t understand.” They discuss Cohn’s early career as a prosecutor and his role as the “mastermind” of the McCarthy purges; his service as a lawyer and fixer for Mafia members, politicians, and celebrities; and an allegation of being involved in sex trafficking.Further reading and listening:  “How Roy Cohn Taught Donald Trump Everything,” by Kai Bird and Susan Goldmark “The Mobster Cosplay of Donald Trump,” by David Remnick “Adapting Oppenheimer’s Life Story to Film, with Biographer Kai Bird,” an episode of The New Yorker Radio Hour “Roy Cohn and the Making of a Winner-Take-All America,” by Naomi FryThe Political Scene draws on the reporting and analysis found in The New Yorker for lively conversations about the big questions in American politics. Join the magazine’s writers and editors as they put into context the latest news—about elections, the economy, the White House, the Supreme Court, and much more. New episodes are available three times a week. Learn more about your ad choices. Visit podcastchoices.com/adchoices