The European Union requires some sort of counterbalance, which depends on states the size of Spain.
Never in its history has Europe been kinder to its little tribes clamoring for their own little desks in Brussels and at the United Nations. Mr. Rajoy was accused of harshly suppressing the illegal “referendum,” in which a minority of Catalans cast ballots in favor of independence. Nearly 900 people were injured in scuffles with police.
But if you want harsh, the Irish could tell you a thing or two about how Europe used to treat separatists. The Dutch had to war with the Spanish for 80 years to secure their independence from the Hapsburgs in the 16th and 17th centuries. A violent separatist cause and the violent counterreaction catalyzed the war that nearly destroyed Europe starting in 1914.
https://www.wsj.com/articles/catalans-cant-stand-up-to-brussels-by-themselves-1507847142?mod=e2tw
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