French political culture has long been seen as a model of leftist militancy, while the left in the United States is often perceived in terms of organizational discontinuity. Yet, the crisis of social democracy today suggests that at a time when the archetypal European welfare state is in danger, critics and citizens interested in understanding or reviving progressive politics are invited to consider the United States, where modes of creative activism recurrently demonstrate potentialities for a renewed leftist culture. Using a transatlantic perspective, this volume identifies activist influence through the designation or rejection of specific intellectual and militant figures across generations, and it examines various narrative modes used by militants to write their own history.