To outsiders it may not seem particularly controversial. But yesterday Spaniards of all stripes were angrily debating a Supreme Court ruling that the Spanish flag must fly outside all public buildings — even in independent-minded regions.

The ruling revived the divisive issue of Spanish unity as those in favour of a centralised state clashed with separatists on internet forums.

“That the Supreme Court has to intervene so that the Spanish flag can fly in Spain is a clear symptom of how neurotic and divided we Spanish are,” a poster called “Atanatos” wrote in Periodista Digital, praising the court’s decision.

Others viewed it as imposition from Madrid. “We live in a democracy and I think it’s unfair to make us fly a flag that we Basques have no good feelings toward,” wrote “Rizzo” on the website of La Vanguardia. “If that flag is placed in my town hall, I’ll be the first to go to a protest march or Spanish flag-burning.”

Foreign visitors are often bewildered at the sheer number and variety of flags on display in Spain. The national flag — red and yellow with the Spanish coat of arms — was adopted only in 1981, when the country returned to democracy after four decades of dictatorship.

However, it must fly alongside the ensigns of the country’s seventeen autonomous regions and two autonomous cities. Some of those still associate the Spanish flag with the repression of the Franco dictatorship, which sought to extinguish the country’s regional identities in favour of a centralised state.

In the most restive regions — Catalonia and the Basque Country — the Spanish flag is often supplanted altogether, bombarded with paint or torn down by supporters of independence.

At public rallies in Spain, still other flags are on display. Right-wing marchers sometimes carry the Spanish flag in use during Franco’s rule, which bears a fascist-style eagle with a sun behind its head.

Leftist marchers will often bear the red, purple and gold standard in use during the Second Republic and scrapped by Franco after his 1936 military coup that sparked the Spanish Civil War.

The Republican flag has become popular with the labour unions and in women’s rights and gay pride marches.

The latest ruling came in response to an appeal by the Basque regional government, which had been ordered by a lower court to fly the Spanish flag outside the academy of its regional police force, the Ertzaintza.

The Basque government argued that it had not flown the Spanish flag outside its police headquarters in more than 20 years. The Supreme Court dismissed the argument, saying that that did not exempt it from doing so.

Lest independent-minded regional governments try to get around the ruling by hanging the Spanish flag in a disused back room or dark cupboard, the Supreme Court specified that it must be hung “permanently” in “a preferential place, inside or outside the building”.

The Basque government said yesterday that it would simply obey the law, without elaborating. But many believed that the Spanish flag will be attacked mercilessly by proindependence protesters if it complied.

There are often violent incidents during the annual fiestas of the Basque city of Bilbao, when the Spanish, Basque and European flags must all be raised above the town hall. Ironically, it is the Ertzaintza riot police that are charged with protecting the Spanish flag during those disturbances, much to the fury of proindependence protesters.

The Mayor of the Catalan town of Matadepera, Jordi Comas, was charged this year with insulting the Spanish flag after refusing to hang it in his town hall.

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