Why is socialism having a moment in America right now — and is it the future of the political left? This week on “The Argument,” Michelle Goldberg talks with Bhaskar Sunkara, the editor of Jacobin magazine, about his new book, “The Socialist Manifesto.” They discuss what distinguishes democratic socialists from liberals, the failures of past socialist movements and why Sunkara favors Bernie Sanders over Elizabeth Warren in 2020.

Then, Ross Douthat and David Leonhardt join Michelle to debate socialism’s role on the political left.