Shared social disadvantage relative to Whites is assumed to motivate inter-minority political behavior but we lack causal evidence. Using a survey experiment of 1,200 African Americans, we prompt respondents to consider group social position when evaluating political commonality with Latinos. The experiment describes racial disparities in a randomized domain (education or housing), varies the description of inequality (either Black versus White, Latino versus White, or Black and Latino versus White), and offers half of the respondents a political cue to test whether shared social disadvantage causes Blacks’ perceptions of political commonality with Latinos. We find little evidence of a causal relationship. We conclude that cross-racial minority political coalitions may be more difficult to activate than previously thought.