A political generation ago, Congressman Jerry Nadler was a backbencher from the Upper West Side. A liberal Democrat with a law degree and a debater’s temperament, he was seen in New York as “a garrulously intelligent, wonkish politician whose previous claims to fame” included “fighting against Donald Trump’s projects on the West Side,” as the Times noted, in a 1999 profile. When House Republicans impeached Bill Clinton, in 1998, for lying about his affair with the former intern Monica Lewinsky, Nadler emerged as one of Clinton’s most ardent and public defenders, trading his obscurity for a brief moment in the national spotlight. The impeachment, he warned in the House Judiciary Committee, was a spectacular misuse of the power granted to Congress by its founding fathers, a “partisan coup d’état.”