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The point of no return is on Sunday. That's when the regional government of Catalonia expects to hold a referendum on the question of independence from Spain. Spanish authorities, though, have declared the vote illegal and are doing everything in their power to stop it from happening.

Spain's government sees the referendum as a rogue, unilateral act by a regional government flouting constitutional order; the Catalan secessionists say they are exercising a fundamental right to self-determination and invoke the dark years of dictatorship from Madrid, when Catalan nationalists were locked in jail and their language suppressed.

“On Oct. 1, citizens of Catalonia will exercise their right to decide whether they want to become a new independent republic, just like other peoples of the world have done before them,” proclaimed Catalan regional president Carles Puigdemont in an op-ed in The Washington Post earlier this week.

Though the move toward a referendum has been in the works for months, if not years, tensions have spiked alarmingly in recent days. Spanish police have arrested 14  senior Catalan officials and confiscated millions of ballots. Spain's online censors have blocked access to pro-independence Catalan websites, including sites that provide information on where to vote. Madrid hopes to make the very act of casting a ballot either impossible or legally precarious. Hundreds of Catalan mayors, though, have said they will do what they can to enable the vote.

“What they’re doing by blocking domain name servers is doing what Turkey does and what China does and what North Korea does,” a spokesman for the Catalan regional government told the Guardian. “No Western democracy does that. The internet is the kingdom of freedom.”

More worryingly, perhaps, Madrid has dispatched thousands of officers of the Guardia Civil, Spain's paramilitary national police force, to move upon polling stations on Sunday. One large detachment has been housed in a giant cruise ship docked in Barcelona's harbor that is emblazoned, now somewhat farcically, with images of Looney Tunes characters. Since the officers' deployment, the image of Tweety Bird has become a symbol of Catalan aspirations.

Despite the literally comic imagery, the prospect of violence and confrontation on the streets hangs over proceedings. The referendum has also led to broader polarization across Spain. Catalonia solidarity protests took place in nearby Basque country, a region with its own long history of separatist aspirations, while nationalists have cheered the mobilization of the Guardia Civil in areas outside Catalonia.

It's playing out internationally, as well. In Washington this week, Spanish Prime Minister Mariano Rajoy won the backing of President Trump, who declared Spain “a great country” that “should remain united.” It was somewhat of a surprise move, given both the State Department's more neutral position and Trump's own support for other anti-status quo causes like Brexit. Julian Assange, the WikiLeaks activist whose organization's work boosted Trump last year, has been campaigning strenuously online in favor of Catalan secession.

Critics of Rajoy argue that his inflexibility and unwillingness to countenance even negotiations with the Catalan secessionists has made the situation worse. “His brand of Spanish nationalism is eerily close to that of erstwhile dictator Francisco Franco, a die-hard centralist for whom the unity and cultural homogeneity of Spain was sacred,” wrote academics Sebastiaan Faber and Bécquer Seguín.

Puigdemont sees it similarly. “The Spanish government has to understand that its behavior is unacceptable from the point of view of democracy and civil rights,” he wrote. “Four decades after the death of the dictator Francisco Franco, we still find that authoritarian instincts rule at the heart of the Madrid government. Respect for minorities is a fundamental human right, and the right of self-determination is an irrevocable right of all nations.”

Though Spain is composed of 17 regions — many with their own distinct cultural and linguistic identities — the country's 1978 constitution deems the nation indivisible. Catalans see their region as a nation in its own right, blessed with a rich history, robust economy and the coastal metropolis of Barcelona as a capital. A 2014 “nonbinding” referendum in Catalonia attracted Madrid's wrath and led to legal proceedings against a number of officials. Rajoy and his allies are all the more furious with the 2017 referendum, which Catalan officials say is binding and would lead to a declaration of independence should the “yes” camp prevail.

“Possibly the central government lost opportunities to tackle the problem five or six years ago, but I do not think that the immobility or strategic errors should be blamed solely on Madrid,” said Carlos Franganillo, Washington correspondent for Spanish broadcaster TVE, to Today's WorldView. “Catalan nationalism has long offered only one solution: A referendum that opens the door to independence. And they know that that is impossible today, because it would force the government to breach the Constitution.”

The irony is that, if allowed to participate in a legally recognized referendum, current polls show that Catalans would likely vote to remain in Spain. But a greater proportion of Catalans simply want the right to have a referendum like the one that took place in Scotland a few years ago.

“Democracy requires consent as well as the rule of law. Constitutional change, especially the right to break away, should be difficult — but not impossible,” noted the Economist. “In Scotland and Quebec, allowing people to have a say did not lead to breakaway. Mr. Rajoy should be less defensive: he should now seek to negotiate a new settlement with Catalonia, while also offering to rewrite the constitution to allow referendums on secession, but only with a clear majority on a high turnout.”

But such a compromise looks nowhere in sight. “I hope events run in a peaceful way, but nobody can rule out violent outbreaks during the weekend,” said Franganillo. “That would greatly complicate the course of this crisis.”

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