The global justice movement reveals a diverse array of emergent publics striving politically for a sustainable world. Working partly from John Dewey, we try to illuminate democratic grounds for knowledge and action in these endeavors. We begin by situating Dewey's ideas in the politics of American history, especially historian John Diggins' countervailing approach to issues of authority, knowledge and opinion. Diggins, against Robert Westbrook and others, contends that Dewey's philosophy of politics chased radical democratic illusions, whereas he might have learned from Charles S. Peirce to uphold the boundary between professional communities and other entities including democratic publics. Dewey saw no democratic alternative to harness the political energy of ordinary people. We argue that Dewey had come to understand that a corporate state system of political economy had come to engulf both the liberal democratic polity and the professions. Dewey's political challenge to the professions and his illumination of the aesthetic ecology of democratic publics prefigure a democratic republican alternative that opens up a new basis for participation in the global justice movement confronting, among other obstacles, a transnational corporate state based in the USA.A Marxist-progressivist notion of the ongoing socialization of markets by corporate capitalism too often reinforces an anti-Populist intellectual sensibility that is coupled with, whether wittingly or not, either a social-democratic elitism or a revolutionary vanguardism. Globalization struggles need, on the contrary, a pragmatic vision of democratic publics instituting a true diversity of policies assuring a world-in-common. The fight for public spaces in the treacherous politics of civil society and global consumerism is a struggle against subjectivization. The fact that corporate state elitism, in the U.S. context, feeds on a rightist version of nationalism does not mean we can junk the history of democratic struggle for a republican alternative to imperialism. By and large, neo-liberal policies "from above" have aggravated various types of inequality and the militaristic turn pursued by some elites compounds not only negative side effects but critical opportunities. Democratic action in and from the United States has to be clear about both place-based forms of life and expanding forms of solidarity in global struggles for democracy and the commons.Our reading of Dewey is strengthened by research that highlights his ecological ontology and its key role in his democratic theory. We argue that globalizing knowledge regimes and their products, such as deforestation, re-institute destructive dualisms that would be transformed by a Deweyan approach that energizes democratic forms of agency and policy. Dewey's essay on "Time and Individuality" is explicated to disclose the radical democratic implications of Deweyan science. We show further that this approach, as a field science and ecological stewardship, provides public alternatives to violence, whether primarily "social" or "environmental". A Deweyan logic of particularity casts in contrasting relief our historical epoch's dominant logic of fungibility, the fetishization of global economic space, and its looming costs. The reclamation and reconstruction of democratic publics are long overdue and requires new regimes of participatory and place-based knowledge opening on the global commons for sustainable life.