I think that the question is why the rich are rich, and how has become rich? If we know the answers of these questions we can answer your question.
If we watch in Spain the map of roads we can watch that If Catalonia get the indepence, Spain will be very poor. Spain needs Catalonia because...
And in Europe the people what prefer? The independence of Catalonia or the union of Spain? Normally in a democratics states, for exemple...
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