This article examines the ways in which Cuba's revolution shaped the changing politics of the Left in the United States. Using critical strategies of transnationalism, it illustrates how a dialogue developed between US activists and Cuban cultural producers, and reveals how Cuba's revolutionary discourse inflected the radical shift towards Third World nationalism. As the post-Bandung global moment brought a network of new political and cultural affiliations, Cuba's state apparatus invested in the manufacture and dissemination of tricontinental politics worldwide. This alternative moral and political imaginary lent authority to Havana's status as leader of the Third World and drew global attention to Cuba's revolutionary model in new thinking on post-colonial identity and culture. This new thinking imbibed the US Left's humanistic turn which challenged standard boundaries of race, class and nation. The dialectical nature of Cuban political discourse and social activism in the United States changed Cuban exigencies while it enticed US dissidents to experience the exception in the western hemisphere that fought for the greater moral good.