The possibility of Catalonia exiting from Spain is dangerous to the integrity of the European Union, even more dangerous than the Brexit. This is what The Daily Telegraph thinks on the matter.
According to ex-prime Minister of France Manuel Valls (born to a Catalonian father), if Madrid allows Catalonia to hold an independence referendum scheduled for October 1st, mostly likely most Catalonians will vote for independence. If that’s the case, this will be the end of the European Union.
At the same time, the situation will aggravate if Madrid uses force. Some Spaniards still remember the Civil War in Spain in 1936-1939, and the Catalonian politicians remind the people about that with photos and videos to promote the idea of gaining the independence from Spain .

The Spanish government should have focused on the political methods. For example, they could have offered Catalonia wider autonomy – like banks, with their own budget and tax system. At the same time, The EU is waiting and passively supporting Madrid without interfering in Spain ’s internal affairs.
Apparently, the problem won’t go anywhere and needs to be resolved. For now, Madrid and Barcelona have been exchanging warnings. While Barcelona promises they will never forget and forgive Madrid for the past, Madrid promises to create and economic border with Catalonia and prevent it from entering the EU as a separate unit.
In the meantime, the Spanish police keep on exempting the papers for the referendum. A couple of days ago, they arrested 2,5 million bulletins, around 4 million envelopes, and 100 ballot boxes.