Muslims are intensely contesting Islamism, or the idea that Islam should not function merely as a religion but should also provide the legal and political framework in society. These struggles can be observed clearly in Indonesia, the world's largest Muslim-majority nation, where conservative and liberal youths compete to determine the model of Islam society should embrace. Conservative youths call for the establishment of an Islamic state in Indonesia, while liberal youths reject this Islamism vision. Few works theorize these contestations among Muslims; yet doing so is crucial because they shape and are in turn shaped by Islam. My dissertation research examines the socialization of believers in a context of competing religious ideologies and asks: How do youth believers become attached to different religious orientations? Instead of conceptualizing the reproduction of young conservatives and liberals as separate processes, this study analyzes how young conservative and liberal Muslims co-.constitute one another's subject positions, and how interactions between them reveals battles over Islamism in concrete, everyday contexts. This project will be conducted in Jakarta, Indonesia's capital city and the site of intense conservative-liberal debates. By examining how Islam gets shaped by relations of power and socialization processes occurring in specific historical moments, this study proposes a way of thinking about Islam and religion without reifying them. Given that youths are instrumental in social movements globally, my analysis of how they come to support a religiously-based movement provides greater insight on how social and political struggles transpire around the world.