Throughout most of American history, the idea of socialism has been a hopeless, often vaguely defined, dream. So distant were its prospects at mid-century that the best definition that socialist periodical Dissent's editors Irving Howe and Lewis Coser could come up with in 1954 was this: "Socialism is the name of our desire."

That may be changing. Public support for socialism is growing. Self-identified socialists such as Senator Bernie Sanders, Ms Alexandria Ocasio-Cortez and Ms Rashida Tlaib are making inroads into the Democratic Party, which political analyst Kevin Phillips once called the world's "second-most enthusiastic capitalist party".