American political theorist, professor emeritus at the Institute for Advanced Study in Princeton, longtime co-editor of Dissent magazine, and one of the most consequential American social-democratic public intellectuals of his generation. Walzer's work has moved across just-war theory, distributive justice, political obligation, the religious sources of political thought, and the practical questions of American left politics, holding together a body of writing whose unity is more a temperament than a system: a willingness to take ordinary moral and political language seriously, to argue from inside actual traditions rather than from a presumed standpoint outside them, and to defend pluralism without slipping into relativism.
Just and Unjust Wars (1977) is the founding text of the modern revival of just-war theory in Anglo-American moral philosophy. Written in part as a response to the Vietnam War, the book argues that the moral assessment of war proceeds best not from abstract first principles but from the historical "war convention" — the accumulated body of judgments through which actual moral communities have distinguished aggression from self-defense, soldiers from civilians, permissible from impermissible tactics. The book has remained the standard starting point for the field for nearly fifty years.
Spheres of Justice (1983) offered the major communitarian alternative to Rawls's distributive framework. Walzer argued that there is no single currency of justice and no single principle of distribution; different spheres (membership, security and welfare, money and commodities, office, hard work, free time, education, kinship and love, divine grace, recognition, political power) operate by different principles internal to the social meanings of the goods at stake. Tyranny consists in the illegitimate conversion of dominance in one sphere into dominance in another — money buying political office, political power dictating religious belief. The argument is pluralist rather than monist about justice, and democratic-socialist in its practical orientation: a just society is one whose internal boundaries between spheres are maintained.
His later books — Interpretation and Social Criticism (1987), Thick and Thin (1994), In God's Shadow (2012, on political ideas in the Hebrew Bible), the multivolume The Jewish Political Tradition (2000–) — continue the project of immanent moral and political reasoning across distinct traditions. He has been the most consistent American philosophical voice for democratic-socialist politics that takes religion, nationhood, and particular community seriously rather than wishing them away.