["Journal of Applied Philosophy, EarlyView. ", "\nABSTRACT\nThis article reflects on Will Kymlicka's account of solidarity and membership through the lens of conflict over public schooling in San Francisco. It contrasts a Marshallian vision of society as a shared possession capable of sustaining democratic solidarity and welfare institutions with an anti‐Marshallian politics that sees the language of shared membership as ideological and exclusionary. Drawing on interview‐based research with local activists, I show how these orientations map onto a divide between ‘moderate’ and ‘progressive’ left actors. Moderates frame schools as a common good and politics as cooperative problem‐solving, while progressives understand educational institutions as sites where racialized and class‐based domination are reproduced, making agonistic struggle necessary. Using grounded normative theory, which reconstructs political judgments from lived experience, I argue that these positions reflect divergent understandings of membership, harm, and fairness rather than simple polarization. Although loyalty to a shared civilization is no longer a plausible basis for solidarity, Marshall's account of rights struggles remains instructive. A post‐Marshallian politics could ground solidarity not in sameness, but in social membership, democratic contestation, and a right to difference within conditions of interdependence.\n"]