Please ask your separatist friends if they would support independence from Spain if they carried a disproportionately small part of the tax burden. I'm guessing they still will.
I can say that they would. The movement towards independence has existed for a long time, and the national question of Catalonia has always been on the table, with several frustated democratic declarations of independence before the dictatorship and a constant reminder from the Catalan Parliament that the Catalan people won't ever give up their right to self determination. It's only recently, however, that the movement has become so big that most Catalans, including many that don't want independence, think that the only way to solve this is to hold a referendum and find out how many people actually want Catalonia to be independent.
While the economy is one of the factors that contributed to the current scenario, the main reason why many Catalans that believed that it was possible for Catalonia to develop adequately within Spain have changed their mind is that recently Spain (the Government, Congress and its Judiciary institutions) have directly attacked all the steps Catalonia was taking to try and feel integrated in Spain. As an example, the attacks to the Catalan educational system (the Spanish Minister of Education said that their purpose was to "spaniardize Catalan children") and to the new 2006 Statute of Autonomy, which brought hundreds of thousands to the streets in Barcelona.
At this point Catalans simply don't think that Spain wants to be a place where they can feel confortable, and the idea of being a normal country that can interact directly and in equality with all the other nations just seems right to most. Shouldn't all nations relate to each other in this way?
