Catalonian regional president and CiU leader Artur Mas gives a thumb up during his party's final rally of the electoral campaign for European elections in Barcelona, Catalonia, north-eastern Spain, 23 May 2014. Alberto Estevez/EPA

The world's eyes are on Catalonia as the region prepares for elections that could pave the way toward independence, but which also threaten to plunge Spain into political crisis and create a serious headache for the European Union. Pro-independence parties are expected to narrowly win an absolute majority of seats in the Catalan parliament — a majority they hope will allow them to declare independence from Spain within 18 months.

Thus, the elections are being seen as a de-facto referendum on Catalan independence, which the Spanish government considers illegitimate and illegal under Spain's constitution. With only days to go, the elections are tight and only a few swing voters will determine the outcome. Meanwhile, Spanish Unionists are launching a hail of doom-laden forecasts for a hypothetical Catalonia.

Luis María Linde, Spain's central bank governor and a European Central Bank board member, warned this week that if it pursues independence, Catalonia would be expelled from the Eurozone and even risk a Greece-style run on its banks, while Spanish Prime Minister Mariano Rajoy said Catalans could lose Spanish citizenship in the event of secession.

Juan Mellen, spokesman for the Catalan Civil Society (SCC), a group which opposes the breakup of Spain, told VICE News that a Catalan government pursuing independence would turn neighbors against one another.

"A [victory for the pro-independence parties] would mean chaos and a state of complete misrule that would result in socioeconomic costs and put at risk the ability for people [in Catalonia] to coexist together, all of which is unprecedented in a modern, Western European country," he said.

The Spanish government has repeatedly denied Catalan Regional President Artur Mas the opportunity to hold a referendum on independence and, as a result, he has hardened his stance, wedding his center-right Democratic Convergence of Catalonia (CDC) party to other left-wing pro-independence parties to dispute regional elections jointly in the Together for Yes coalition.

Catalan independence has witnessed a dramatic increase in support during the last five years, but, still, only around 50 percent of the region's population supports independence, according to most polls. Considerably more Catalans, approximately 70 percent, support the right to a referendum on secession. If it wins, Together for Yes plans to lay the groundwork for secession and hold the plebiscite Madrid has prohibited.

Alongside a push for recognition of Catalonia's cultural and linguistic differences, much of this support is based on the argument that separation from Spain would allow for better governance and increased economic prosperity.

Catalonia accounts for almost a fifth of Spain's gross domestic product, and around 16 percent of the national population. Separatist parties argue that erasing the deficit between what Madrid collects in taxes and what is returned for public spending — as much as 16 billion, or eight percent of GDP, according to their estimates — would help finance far-reaching social spending and lessen the hardship of austerity.

For Elisenda Paulize, dean of economics at Barcelona University, should Catalonia secede, it would be able to strengthen its export-driven economy, but also affect more fundamental changes and overhaul dysfunctional elements of the Spanish state.

"[Independence] would provide the opportunity to redefine the relationship between businesses and government institutions, which is very corrupt in Spain," she told VICE News. "And at the same time tackle the huge social inequality that exists in Spain and is among the most extreme in Europe."

In a 2012 interview, Mas said a Catalonia with control of its own tax base would be able to mirror the economic success of Northern European countries, focus on innovation and aim to become the "Netherlands of the south."

But critics say that separatist politicians are selling a dangerous fiction.

Ángel Ubide, senior fellow at the Peterson Institute for International Economics, said an independent Catalonia would suffer "very negative" economic costs in the short term.

"The excess contribution paid by Catalonia is minor, around two or three billion euros," he told VICE News. "If Catalonia becomes independent the reduction in its tax base could cancel out this surplus."

An independent Catalonia's status in the European Union is fundamental. Ferran Requejo, political scientist at the Pompeu Fabra University and member of the Advisory Council for National Transition (CATN), said that the secessionist camp may gamble and hope it can bypass the need for a negotiated exit by forcing the issue internationally.

"Rather than [allying] with parties in Spain, the strategy would be to look for alliances in the EU," he said. "The idea being that it's not in the EU's interest to have this problem."

Pro-independence delegates have traveled to the parliaments of Denmark, Ireland, Uruguay and Belgium, as well as the US House of Representatives, in recent months. The Scottish National Party, which hopes to gain full autonomy from the UK after narrowly losing a 2014 referendum on independence, this week gave its support to the Catalan cause, calling on Madrid to allow a plebiscite.

"Catalonia is a nation, and has a right to choose, that is absolutely clear," said Alyn Smith, a member of the European Parliament from Scotland who is heading an election observer mission. "The alternative is simply anti-democratic, anti-European and potentially explosive."

However, over the last month, German Chancellor Angela Merkel, British Prime Minister David Cameron and US President Barack Obama all expressed support for Spanish unity.

The European Commission has also suggested any state that declared independence unilaterally would have to reapply for membership. But the commission has not yet adopted an official position.

Ignasi Guardans is a former member of Mas' CDC party, for which he acted as a member of the European Parliament. He said there is little likelihood of other member states recognizing an independent Catalonia without Spain's blessing.

"If an EU country recognized the unilateral independence of a territory belonging to another member state, in violation of said state's national parliament and constitution, we would enter a state of chaos," he told VICE News. "Whoever does this would have a serious confrontation not only with this Spanish government — or any Spanish government — but with the governments of all countries with any kind of territorial dispute."

This week Mas called for negotiation, warning that a unilateral break would amount to a "joint suicide" for both factions.

Should Mas' coalition win and he continue as president, he will likely prefer to negotiate, a position more in-keeping with his party line. Critics dismiss plans for a unilateral declaration of independence as a ploy to force a compromise with Madrid in the future.

However, if Together for Yes requires support from the left-wing Popular Unity Candidacy (CUP) party, Mas could be deposed in favor of a more hardline candidate. Even if Mas were to remain president, he could be dependent on CUP support. According to Nick Greenwood, political analyst at Madrid-based financial consultancy AFI, this might limit his ability to consider a negotiated exit or mean greater pressure for an early unilateral declaration of independence.

The result would likely be the government employing some of the formidable array of judicial firepower at its disposal to block a secessionist Catalan parliament.

Spanish Prime Minister Rajoy's right-wing government is rushing to push through legislation that will grant the constitutional court the power to suspend Mas, or any other elected representative, who does not comply with the court's ruling. Madrid could also employ an article in the constitution to wrest control from Catalan parliament outright. However, Greenwood claims, the government will tread carefully for fear of escalating the situation and "creating a siege mentality."

With the government pressing ahead with plans to block the independence movement judicially, and unionists of all stripes warning of serious instability, many in Catalonia claim the SCC and others are running a scare campaign, a charge Mellen denies.

"Call it what you want, but if I see someone standing on the train tracks, I'm going to say: 'Be careful, or you'll get run over,'" he said. "We cannot say nothing and pretend there won't be consequences because the independentists see everything through rose-tinted glasses."

But supporters of Catalan independence argue that the risks under discussion could all be avoided if the government agreed to negotiate.

"It's not a question of these being the costs of independence, rather these are economic costs that would be brought to bear if [the government] acts on its threats of retaliation," Paulize said.

"Not coming to a civilized agreement would also hurt [Spain]. If Catalonia is excluded from international institutions, it would mean it would be unable to negotiate assuming a share of Spain's assets and debt. That would leave Spain with an unmanageable level of debt."

For Paulize, Spain's hardline stance is likely a bluff.

"I don't think these threats are credible, because if Spain follows them through it will hurt them just as much," she said. "But if it has the effect of changing the vote so that independence can't win the votes [it needs for a majority] on Sunday, it will have worked perfectly."

The Spanish government and the Catalan independence parties are engaged in brinkmanship. Both factions have plenty to lose in the case of Catalonia attempting a forced exit, both believe they can call the other's bluff, and, for the time being at least, neither is prepared to blink.

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