re: Are we really talking about a modern European country breaking apart in Civil War?

The Catalons are pro-eu like Scotland. Catalonia is the wealthiest region in the country and home to Barcelona, one of the biggest tourism attractions in Europe. Since all EU countries use the same currency, are at peace, and can trade and travel freely with one-another, the risk of partition simply isn’t there anymore. Before, regions that didn't like each other might band together into larger nation states for protection and for better access to markets, but now those concerns are largely gone thanks to NATO and the Eurozone. Look for more decentralization of the great nation states, like Germany and Italy especially, in coming years while a simultaneous movement looks to turn Europe from simply an economic union to a federal sovereign. In fact, last decade, Europe nearly voted in favor a referendum to establish a constitutional government, but Germany, France, and Italy rejected it by narrow margins, and England by a wider margin. With Brexit and rising support for a central government to deal with issues like fiscal policy and immigration, there is a really good chance the European Union could become something resembling a United States of Europe in the next 10 years.