Judge Manuel Marchena presided over the trial of Catalan separatist leaders at the Supreme Court in Madrid on Feb. 12. (Emilio Naranjo/AFP/Getty Images)

Naomi Mezey is a law professor at Georgetown University, where she teaches nationalism and cultural identity. She is currently a visiting scholar at the Universistat Pompeu Fabra in Barcelona.

Tensions on all sides are high in Spain as the trial of the century gets underway this week, with a dozen Catalan leaders facing charges of rebellion and sedition for promoting a 2017 independence referendum. But Catalonia’s attempt to break free and Spain’s reaction are relevant well beyond the country’s borders.

Even more than Brexit, Spain’s most serious constitutional crisis since its transition to democracy in the 1970s could presage new sovereignty disputes and democratic instability. And the 12 defendants — who are former Catalan government officials, members of parliament and civil society leaders — won’t be alone in facing a verdict. The very viability of democratic states of diverse and divided citizenry is also on trial. At its core, Spain’s trial is about whether democracies can manage profound disagreement among their citizens and maintain their commitment to democracy.

In the face of demands by constituent groups for greater autonomy, rights or recognition, even democratic states are often tempted to react to nationalist demands with an authoritarian nationalism of their own, often a toxic and ultimately divisive tonic of national “unity.” Hence the appeal of populist nationalism around the world. This is a particular challenge for Spain, where, in addition to its historically unresolved relationship to fascism, the far-right Vox party has emerged as a new political force, serving as the “peoples’ prosecutor” in the trial and joining with other right-of-center parties to push a vindictive approach to Catalan independence. Last Sunday’s rally organized by these parties made abundantly clear that this is a war of competing nationalisms.

The political scientist Benedict Anderson famously defined a nation as “an imagined political community,” a group of people with a deeply shared identity that binds them together with others whom they will likely never meet but whom they imagine as fellow compatriots. But if we imagine our co-nationals through media, discourse and shared culture, as Anderson envisioned, it is no wonder that our political communities are increasingly fractured and tribal. In Catalonia, as recently as 2005, not much more than 12 percent of Catalans supported independence and most Catalans thought of themselves of belonging to two compatible political communities —Catalonia and Spain. Since 2012, support for independence in Catalonia has hovered between 45 and 50 percent.

So what happened to fray the attachment of so many Catalans to Spain? Many in Catalonia point to the bruising political battle begun in 2005 to pass a revised statute of autonomy, the region’s governing document under the Spanish Constitution. Over a period of years, the statute was negotiated and renegotiated, passed by both the Catalan and Spanish parliaments, approved by the public, and supported by then-Spanish President José Luis Rodríguez Zapatero. Then, in 2010, much of it was struck down by the Constitutional Court. This ruling and the discourse that surrounded it aggravated ancient and modern antipathies, ushered more Catalan separatists into political office and hastened the declining relationship between Catalonia and Spain.

On Oct. 1, 2017, Catalonia’s regional government held a referendum on whether Catalonia should leave Spain to form an independent republic. On the basis of that controversial vote, in which most of those who opposed independence did not participate, Catalonia declared independence. Spain nullified the referendum and used a constitutional “nuclear option” to dissolve the Catalan government. Things might have ended there, or at least reached a detente. But Spain confronted the regional nationalism with its own nationalism and all the powers of the state: police, prison and the heavy hand of criminal law.

Just as Brexit is Britain’s “drama of departure,” as Fintan O’Toole noted in the Guardian, this trial marks the climax of Spain’s drama of forced inclusion. Both dramas are replete with unintended ironies and self-defeating nationalism — to demand Catalonia’s inclusion in the name of a strong, unitary Spain by keeping its political and civic leaders in pretrial detention for a year and threatening decades of imprisonment seems destined to be counterproductive. On the other hand, it can’t be right that the Catalan independence referendum was “just” a democratic exercise, political speech or a gambit to force Spain to renegotiate Catalonia’s statute of autonomy, as defenders often insist. It may have been all those things, but it was also a political act of secession that was meant to have consequences.

So was the independence referendum legal? Almost certainly not. Spain, like most countries, does not provide constitutional or clear legal mechanisms for secession, and the Constitutional Court had declared the referendum unconstitutional before it took place. But was it criminal? Again, almost certainly not. Not long ago, Spain decriminalized unauthorized referendums, which is why the defendants are charged with rebellion and sedition. But rebellion, the most serious charge, specifically requires violence in relation to declaring “independence of any part of the national territory,” and it seems fairly evident that the only real violence that occurred was caused by the national police who were sent in to forcibly stop the referendum.

Although this is a legal drama, the law is not well equipped to answer the most pressing questions that confront Spain and diverse, divided democracies like it. In Spain, as in the United States, the law, and especially our courts, are often called upon to decide our deepest differences for us. Spain’s trial is likely to show us that courts are not only a poor place to reach amicable resolutions but they also are prone to entrench our grievances. It may also offer another lesson: that the more politicized our judicial selection, the less trustworthy courts become and the less effective they are at the hardest decisions we ask them to make.

The real question is how do we live together peaceably or part with civility. This is a question that confronts all democracies because all modern states are multinational these days; they contain many political communities and various minority populations that are different from the majority by virtue of their race, religion, language or culture. This would also be true of an independent Catalonia. It would find itself with half its population still deeply committed to Spain, with immigrants and new linguistic minorities clamoring for rights, recognition and maybe secession. Nationalism thrives on fantasies to which we are all susceptible, on nostalgic dreams of past suffering or future grandeur; but nationalist fantasies can’t create unity and more often undermine it.

The appeal, and the fragility, of pluralist democracies flow from the commitment to both the political stability of a culturally-diverse country and the rights of internal groups to maintain and assert their cultural distinctiveness. It is the demands of pluralism that confronts Spain at this moment. Its ability to acknowledge and nourish that pluralism without being threatened by it will determine whether Spain is able to defend its democracy and adapt it to the 21st century.

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