A great article about the politics of labor from Binyamin Appelbaum in The New York Times:

This myopic focus on factory jobs distracts from another, simpler way to help working Americans: Improve the conditions of the work they actually do. Fast-food servers scrape by on minimum wage; contract workers are denied benefits; child-care providers have no paid leave to spend with their own children.

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The enduring political focus on factory workers partly reflects the low profile of the new working class. Instead of white men who make stuff, the group is increasingly made up of minority women who serve people.... The old working class still controls the megaphone of the labor movement, in part because unions have struggled to organize service workers. Manufacturing was, logistically speaking, easier to organize. There were lots of workers at each factory, and most knew one another. Service work is more dispersed and done in smaller crews. Workers living in the same city and employed by the same retail chain, for example, would likely know only a handful of their compatriots. Fostering a sense of trust and shared purpose under these conditions is difficult.