Class struggle has always had a soundtrack. A hundred years ago, the Industrial Workers of the World (IWW) had Joe Hill, author of popular labor folk songs like “The Preacher and the Slave” and “There’s Power in a Union.” American Communists of the 1930s had baritone Paul Robeson, and the activists of the 1960s and 1970s had folksy Joan Baez and Phil Ochs. Today’s striking autoworkers have GmacCash.

Fifty thousand workers at General Motors (GM) are entering week four of a massive strike. GM is losing millions, but won’t give in to union negotiators. Workers’ major demand is an end to the multitiered contracts which screw over new and temporary workers — who now have to work for eight years before reaching full pay — and undermine the solidarity and wages of the whole union.

When the United Autoworkers (UAW) and other industrial unions were built in the 1930s and 1940s, millions of workers went on strike each year, coming together across lines of skill, ethnicity, and geography. Since the 1970s, however, union membership and strike participation have declined precipitously, while millions of manufacturing jobs have been relocated to nonunion plants and income inequality soars. In 2017, only 25,000 workers participated in major work stoppages, the second lowest year on record.