Raul Romeva, Together for Yes coalition, Catalonia, Spain

The people of Catalonia in north east Spain are about to vote in a local election which has become a de facto poll on independence. The outcome could plunge Spain and Europe into a prolonged period of constitutional uncertainty. Stephen Sackur asks Raul Romeva, a leader of the pro-independence coalition, why the obsession with secession at a time when Europe is struggling with economic stagnation and mass migration.