Just when it seemed as if the election of Donald Trump had rendered his supporters incoherent with triumphalism and his detractors incoherent with rage—thereby dumbing-down political conversation for a long time to come—something different and more interesting happened. A genuine debate has sprung up among liberals and progressives about the subject of the hour: identity politics.

Jump-started by a short manifesto called The Once and Future Liberal: After Identity Politics by Columbia University professor Mark Lilla, it’s a conversation worth following for reasons beyond partisanship. As in his New York Times essay published 10 days after Trump’s electoral victory, Lilla’s purpose in this broadside is two-fold: to excoriate identity politics, sometimes called “identity liberalism,” and to convince his “fellow liberals that their current way of looking at the country, speaking to it, teaching the young, and engaging in practical politics has been misguided and counterproductive.”