Brussels' Perspective on Catalonia and the Contradictions of the European Union

As the face-off between Madrid and Barcelona continues, we explore how this happened and where it might end. Marc Weller, chair of the independent commission on Catalan independence, explains the legal background and historian Brendan Simms sets out what is at stake for European politics. Could this be the crisis that brings the whole thing crashing down? With Helen Thompson and Chris Brooke.