This chapter shows how human sciences researchers in Puerto Rico faced pressure to abandon earlier traditions and embrace the methods and biomedical enterprise of the United States empire’s scientific modernity. Drawing on the history of mental testing and inmate assessment as well as designs for a new penitentiary, the chapter contends that while mid twentieth-century US-American social science engaged in intense processes of othering that aligned with imperial expansion, Puerto Rican social scientists combined US-American psychometrics with older Spanish ethnographic traditions that powerfully resurfaced in the 1940s. These diagnostic and descriptive tools revealed that incarcerated people required discipline, tutelage, and treatment, but that they also had redemptive potential regardless of social difference. Social scientists put mental test results into dialogue with ethnographic narratives of convicts to forge what to them were forward-looking treatment programs, illustrating how racialized racelessness and intersubjective exchanges transformed Puerto Rican corrections for a time. The result was a blended, “creole” nationalist science with decolonial aspirations, although one that was colonial-populist in practice.

During the 1980s and 1990s, Indigenous Chamorro political leaders and activists challenged United States imperialism on Guam, particularly the issues of heavy militarization and increased immigrant and settler presence. Influenced by Indigenous decolonization movements throughout the Pacific, Chamorros engaged in the political process of self-determination as stipulated by Chapter XI of the United Nations Charter. Through the Guam Commonwealth Movement, they chose to articulate their right to self-determination as an Indigenous people, emphasizing Indigenous political rights and culture within an island whose population was increasingly multicultural. Although the movement was ultimately stalled by the US Congress due to its perceived unconstitutionality, the quest for Chamorro self-determination reveals the limitations of the UN saltwater thesis for colonized Indigenous peoples living within settler colonial islands, demonstrates how articulations of self-determination become inextricable from Indigenous rights, and illustrates how US imperialism in the Pacific persists well into the twenty-first century.