What has happened in Europe is basically this: Germany is a pimp, and he wanted to fuck Spain, Greece, Portugal and Italy who were a little bit naughty but in the end we were just cock-teasing them. What Germany did was basically give us dope for free in the beginning, then at a very low price, and once we became addicts at an stratospheric price. Right now we are pawning whatever worth we have to pay the debt back before we get punished, but is so big that there is no way we will do it. Instead Germany has been so kind that has let us pay in flesh and now we have become Germany's bitches. That's the issue, long things make short. But remember something, Spain my sink, but we are big enough to take the rest of Europe with us to the bottom so we won´t be alone down there
About a possible civil war here. Consider since we kicked the frogs out up to now we had: 3 civil wars in the 18th century:
http://en.wikipedia.org/wiki/Carlist_Wars, one attempt to create a confederation of cities-states in the ancient greek way
http://en.wikipedia.org/wiki/Cantonal_Revolution the fall of the monarchy and the rise of a republic, the restoration of the monarchy, one military dictature and the big civil war that you all must have heard about and which was a prelude to the WWII:
http://en.wikipedia.org/wiki/Spanish_Civil_War None of this wars were between peoples or territories, fights had an ideological background or were between two factions of claimants to the throne. All peoples and territories in Spain has suffered equally tirany and opression from the government. There were regional elections in Catalonia last month, the conservative catalan nationalist had been in the office for two years and was losing popular support because the cuts in health and education budgets, corruption, taxes, etc. There were fierce demonstrations of people against their policies to the point that the president of the autonomous government had to arrive once to the parlament on a helicopter because it was surrounded by protesters! Then he shifted the speech to Madrid rob us, and central government shifted to catalans are bla bla bla and it was the perfect courtain to hide the cases of corruption that are popping up like mushrooms and their lack of control on the situation.
About cultural conflicts Spain was even in the most repressive periods pretty much more tolerant than other western countries; for instance the situation of minority languages in UK (scotish, welsh, isle of mannish?, irish or cornish), Germany (Sorbish, Frisian, Danish, Bavarian, Platt-Deutsch...) not to talk about France (Occitan, Corsic, Breton, Basque, Catalan, Alsatian...) where local and minority languages has been almost anihilated or have no legal status nor take part in the official curriculum in schools, high schools and universities.
In short, anything is possible, specially in times when resources are scarce and people have to fight over the leftovers, and there is a strong nationalistic feeling in the periphery of the country but: we have no radical far right organized scene with members in the parliament as they do in Greece and most European countries, we don´t have a strong communist party, our anarchist scene is small, most people are like sheeps voting PP or PSOE in the way americans do with Republicans and Democrats (and their regional nationalist versions), and people are much more moderate than they're in France or Greece. I hesitate an armed conflict could take place here, if it would thinkgs should be already pretty fucked up in the continent and in the case it took place place I would bet for an ideological war (left vs right) more than some kind of independence war.