You sometimes hear about "intersectionality", the ways in which systems of oppression like patriarchy and racism overlap, and so the interests of those working against them also intersect. You almost never hear about the intersectionality of economic class. It's as if today's "liberals" (so-called) and Democrats don't actually care whether society is built as an oppressive hierarchy, just so long as being an oppressor is an equal-opportunity position. It's no wonder that since the days of the Reagan Democrats -- indeed, going back to the 1960s -- the Republicans have been able to catch this demographic "on the rebound" as it were, after the Democrats dumped the to pursue identity politics.
(Contrast this with how the radical Black Panthers reached out to work with poor whites; and for interesting history, read Kenneth D. Durr's Behind the Backlash: White Working Class Politics in Baltimore, 1940-1980.) The reunion that Sanders suggests would be a powerful thing -- and those in power now sure as hell don't want that.
These kinds of statements are the name of the game for today’s Democratic elite. The party has established a clear line on the white wage-earning class: they’re all either dying (demographically or literally), irrelevant in an increasingly nonwhite country, or so hopelessly racist they can go off themselves with a Miller High Life-prescription-painkiller cocktail for all they care. As liberal hero and Sanders nemesis Barney Frank put it a couple of weeks ago, “the likelihood that fifty-eight-year-old coal miners are going to become the solar engineers of the future is nil.”
The problem with this line is not just that it’s gross and elitist — it’s that it’s not even true. The working class is bigger than ever, is still really white, and is broadly supportive of a progressive populist agenda.
It just turns out that the Democratic Party outside of Sanders isn’t too interested in that agenda. And it’s even less interested in that specific chunk of the working class that forces liberals to confront head on the naked brutality of the economic system they cherish.
After decades of being told white workers would never support socialism because they’re racist, we’re now told that they support the socialist candidate because they are racist. Yes, this is where liberals are in the year 2016.