The Chicago Teachers Union is going on strike tomorrow. But they aren’t going alone.

The union struck in 2012, claiming to fight not just for themselves but for a broad social justice agenda in defense of public schools and all public services. They emerged victorious over Mayor Rahm Emanuel and the Chicago Public Schools, who wanted to further erode teachers’ power in the schools and institute more free market-friendly reforms. At a time when the labor movement was in dire straits, the win was an inspiration to unionists around the country.

But since then, the union has suffered defeat after defeat: forty-nine school closures, rounds of layoffs, devastating budget cuts. And Illinois’ new Republican governor, private equity mogul Bruce Rauner, has carried out a disastrous agenda of austerity, holding the state budget hostage unless legislators agree to major rollbacks of union rights.