PARIS — What is France to do, as neighbors, and we Europeans, as fellow citizens, faced with the declaration of independence of Catalonia? It undermines a large European democracy on our border, Spain, and places us in the face of an unprecedented challenge. Within what right do we say "yes" or "no" when the nationalism that is expressed is democratic — it is based on votes — respectful of individual freedom and even open to foreigners?

I was faced with the Catalan independence movement at the beginning of the year 2000 in unusual circumstances. Invited to Barcelona by the French Institute for a conference on immigration and Europe, I received an invitation to meet Jordi Pujol, then President of the 'Generality' and figure of the independence movement. The next morning, when I arrived at his office, my first surprise was not only to find Mr Pujol there, but also a part of his government, responsible for its administration and the head of the Catalan police force in uniform.

After a brief discussion of the situation in France, Pujol stopped suddenly and told me: "Mr. Professor, I have, we have only one question to ask you. Catalonia receives a lot of immigrants. But these foreigners, when they come to us, they do not want to learn Catalan, they want to speak Castilian. I lead a small country isolated between two big ones. How am I to ensure that these immigrants learn Catalan?"

I was doubly taken aback, but had a response ready: "Let the children come as soon as possible, do not block, as others do, requests for family reunification: in school the children will learn Catalan and will speak Catalan to their parents. So that means the parents will learn Catalan." I saw his eyes light up. He thanked me and stood up. Our meeting was finished.

Since then, I have followed the fate of Catalonia with interest, and this movement that aspires to see it recognized as an independent republic, open to foreigners when they want to learn the language. This open-minded nationalism has reminded me, most of all, of the Quebecois separatists. And, today, it is perhaps toward Quebec and Canada that Spain should turn to respond to the current situation.

The Constitution is not only a written text.

At the time of the second independence referendum of 1995, the Supreme Court of Canada was faced with a request for an opinion by the Governor of Canada. Just as that of Spain, the constitution of Canada does not provide the possibility of secession through a referendum for independence. But the Canadian court had refused to simply state that. Confronted by a powerful movement claiming popular democratic sovereignty, the Court issued, in August 1998, a unanimous decision, summarized in its first paragraph that was bound to go down in history.

It stated that the Constitution is not only a written text, but that it "embraces the entire global system of rules and principles which govern the exercise of constitutional authority." The Canadian Court added that a superficial and formal reading of the Constitution could mislead. It ruled that it was therefore appropriate to do a more thorough review of the underlying principles that dictate the whole of the Constitution. This review had identified four principles: federalism, democracy, constitutionalism and the rule of law, to which is added the respect of minorities.

Finally, the Court stated that if a clear Quebecois majority, in response to a clear question, voted for the secession, then, on the basis of these four principles, discussions with the federal power in Canada should be opened. The Court had however set conditions for the recognition of the secession of Quebec: not unilateral action, a referendum on a clear question, with a clear answer — even if it did not reject it by principle or by a formal reading of the Constitution.

The court also added guarantees for the fundamental civil liberties and the right of minorities: these ensured that a majority will, even clearly expressed by the Quebecois, can never incriminate the rights and the status of non-Francophone citizens or non-nationalists from Quebec. This clear and balanced decision was well received by all the parties present, and has done much to ease tensions over Quebecois separatist claims that linger today in Canada.

Unfortunately, so far, a clear lack of such vision and reason in Spain today is making the Catalan crisis worse, and strengthening the independence movement. Rather than blindly backing Spanish Prime Minister Mariano Rajoy. and add their threats to his threats, the likes of European Union chief Jean-Claude Juncker and French President Emmanuel Macron should take inspiration from the Constitutional Court in Canada from 20 years ago. To govern is to know how to react to unforeseen situations with unprecedented solutions.

The guarantee, both present and future, that fundamental freedoms are respected must be the basis of a solution to a crisis that European leaders must tackle briskly. Otherwise, the very idea of Europe may soon be at risk.

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