... [In 1996] the liberal writer Michael Tomasky published "Left for Dead," which argued that the progressive movement was being ruined by multicultural identity politics. Democrats have lost the ability to talk to Americans collectively, Tomasky wrote, and seem to be a collection of aggrieved out-groups: feminists, blacks, gays and so on.

At the time, Bernstein and Tomasky were lonely voices on the left, and the multiculturalists struck back. For example, Martin Duberman slammed Tomasky's book in The Nation, and defended multiculturalism:

"The radical redefinitions of gender and sexuality that are under discussion in feminist and queer circles contain a potentially transformative challenge to all 'regimes of the normal.' The work of theorists like Eve Kosofsky Sedgwick, Jeffrey Weeks, Marjorie Garber and Judith Butler represents a deliberate systemic affront to fixed modes of being and patterns of power. They offer brilliant (if not incontrovertible) postulates about such universal matters as the historicity and fluidity of sexual desire, the performative nature of gender, and the multiplicity of impulses, narratives and loyalties that lie within us all."

Duberman insisted that postmodern multicultural theorizing would transform politics, but today his gaseous review reads as if it came from a different era, like an embarrassing glimpse of leisure suits in an old home movie.

That's because over the past few years, multiculturalism has faded away. A different sort of liberalism is taking over the Democratic Party....