As mandates for social inclusion of people with intellectual disabilities remain unfulfilled, many scholars question whether the concept of inclusion is to blame. Critics worry that quantitative measurements of inclusion miss what should count: a meaningful life gained from a sense of belonging. We argue that both concepts - inclusion and belonging - embody a communitarian ethos in which citizens mirror the values of their community. In contrast, Chantal Mouffe's radical democratic approach to inclusion emphasizes the importance of difference and the inevitability of exclusion. Mouffe thus offers a way to broaden our approach to social inclusion in the twenty-first century.