Leaders from the Service Employees International Union, the United Auto Workers, American Federation of Teachers, and UNITE HERE announced March 14 a new coalition to organize graduate student workers at private universities.

A 2016 labor board decision involving Columbia University paved the way for graduate workers to unionize at private colleges. Students and unions think that a Republican-majority NLRB could overturn that ruling. By working together, the four major unions are pursuing alternatives that don’t involve the National Labor Relations...