This chapter delves into the rise and fall of contemporary Chilean nationalism through an in-depth case study of the Movimiento Social Patriota (MSP). Established in 2017, MSP sought to defend national identity and social justice against what it perceived as the decay of Western liberalism. This study examines MSP's ideological foundations, significant actions, and public interventions, including their provocative protests and campaigns. Utilizing ethnographic research, document analysis, and interviews, this chapter reveals the complexities of MSP’s doctrines and the social dynamics within the movement. Furthermore, it contextualizes MSP within the broader historical and socio-political landscape of Chilean nationalism, tracing its roots back to the late nineteenth century. The chapter also addresses the implications of MSP's rise for contemporary political discourse in Chile, particularly in light of increasing concerns over immigration and national sovereignty.