We investigate how vertical unity within a community interacts with horizontal class divisions of an unequal income distribution. Community is conceptualized in terms of a public good to which all those in the community have equal access, but from which outsiders are excluded. We formulate the idea of redistributive tension, or class antagonism, in terms of the costs that poorer individuals would be willing to impose on the rich, to achieve a given gain in personal income. Our conclusion is that the nominal distribution of income could give a misleading picture of tensions in society, both within and across communities. Ideologies of community solidarity may well trump those of class solidarity because of the implicit sharing of community resources brought about by community-specific public goods. Greater economic mobility of particular types may actually exacerbate class tensions instead of attenuating them. We illustrate our theoretical results with a discussion of a number of historical episodes of shifting class tensions and alliances.