Much of the urban research on the daily experiences of Black men in American society has focused on Black men as perpetrators, as victims of street and gang violence, or with some carceral connection. These earlier studies highlight how racist tropes of Black men as dangerous and thus to be feared situate Black men for continuous, targeted, and aggressive actions by the state and other social actors. This places a social tax on Black men who are then bound to exercises of embodied negotiations in public social spaces where they navigate both being shunned and “disappeared” while also hyper-visible. Drawing on ethnographic data collected across several years, this article examines how Black men are targeted for aggression in mobile public spaces in Chicago, Illinois. We use public transportation as a space of interrogation because of the uniqueness of mobile places where riders and transit personnel are temporarily confined while mobile and with limited options to escape the dangers of racism and racial aggression. In these spaces, we find that (1) Black men are threatened with harm, (2) their bodies are treated as sites of fear, and (3) their well-being is risked through an institutional breach of duty to provide safety for them as passengers and transit personnel.