This article addresses the challenges of justifying restrictions on migration given a rejection of nationalism as a defensible mode of political integration. Specifically, it focuses on constitutional patriotism, which is proposed as a means of making robust democratic practice possible in diverse contexts. Given that constitutional patriotism represents a commitment to universal principles as a source of attachment rather than the binding sentiment of nationalism, can we continue to rely on nationally defined and controlled migration practices? This article argues that, appropriately understood, constitutional patriotism implies a commitment to much freer movement of individuals across political boundaries than theorists have previously acknowledged. Applying such an approach, however, provokes some challenges to the sustainability of shared rule informed by principles rather than identity. This seeming paradox may mean that constitutional patriotism is more difficult to implement, and highlights practical challenges surrounding the liberalisation of border controls that are pertinent to theorists concerned with post-national citizenship more broadly conceived.