Sukarno once employed the phrase “character-building, nation-building” as an ideological framework for public policy intended to mobilize the newly independent polity. The chapter aims to explore the revolusi mental with the memory of Sukarno-style nation-building as a way to illuminate the problems of a country like Indonesia. For most Indonesia specialists, the relationship between Islam and the Indonesian polity has been a matter of intense interest. Indonesian Muslims are optimistic in welcoming all future challenges in the spirit of both Islam and Pancasila. Islam involves, in fact, a significant participatory element, a pillar and source of Indonesian values. Populism has posed a challenge to the legitimacy currently enjoyed by the Indonesian polity, in part because it has emerged as a “post-truth” movement. Nation-building in Indonesia undoubtedly is moving toward greater democratization and the progressive realization of human rights. In most cases, those debates echo many of the experiences of the Indonesian intellectuals themselves.