With her recent article in the Washington Post,, Sheri Berman has resuscitated a genre that’s lain largely dormant for decades: the liberal anti-socialist polemic.

Berman’s column ranges across more than a century of socialist history to construct an opposition between two trends on the Left: social democrats, who she likes, and democratic socialists, who she very much does not. While democratic socialists have stubbornly clung to the ill-defined dream of transcending capitalism, social democrats have pragmatically accepted that capitalism is here to stay and gotten down to the business of reforming it. Her conclusion is simple: people should reject democratic socialists like Alexandria Ocasio-Cortez in favor of social democrats like Joe Biden, whose acceptance of capitalism and whose amenability to compromise means they can actually deliver the goods.

Yet while Berman is correct that Ocasio-Cortez is a very different kind of politician than Biden, the difference between the two doesn’t come down to who offers “viable solutions.” Ocasio-Cortez’s popularity stems directly from her advocacy of a whole host of concrete reforms, from Medicare for All to ending ICE.