While Americans commemorate Sept. 11 by putting aside differences, Spaniards mark the day by letting divisions flare.

Sept. 11 is Catalonia’s National Day, when the 7-million-strong semi-autonomous community commemorates the anniversary of their defeat by Spanish troops in 1714, which ended Catalan independence.

Thousands of protesters plan to take to the streets Tuesday evening in Barcelona, the largest city within Catalonia, urging independence for the territory. This year, the annual demonstrations promise to be even larger than in the past, as frustrations over unemployment and the ongoing recession have escalated tensions with Spain.

Many also took to Twitter, where the hashtag “#freedomforcatalonia” was trending in Barcelona:

(Screenshot: Trendsmap)

Catalonia deserves to be a new state in the European Union for thousand of reasons.The most important: people want it. #freedomforcatalonia

— Jesús Pastor ||*|| (@jesuspastorGI) September 10, 2012

Catalonia, next state in Europe! That is what we are asking for. We claim for our independence!#freedomforcatalonia #11s2012

— Laura Borràs (@LauraBorras) September 10, 2012

Others posted pro-Catalan images to Instagram and other services, prominently displaying the region’s red and yellow striped flag:

(Screenshot: Twitter)

(Screenshot: Twitter)

The separatism stems in part from the perception among Catalans that they pay more than their fair share of taxes to Spain’s central government than they receive back in services.

“Economists calculate that Catalans pay 12 billion euros more in taxes per year to Madrid than they receive back for services like schools and hospitals,” Reuters reports.

The Web site espolimetre.cat (or “Theft meter”) purports to show the “fiscal transfer” between Catalonia and Spain. Earlier this spring, Catalans began a social-media campaign to protest toll roads, vowing, “#novullpagar — “I won’t pay.”

(Screenshot: espolimetre.cat)

In August, however, the region asked Madrid for a $6-billion bailout to cover budget deficits, although Catalan regional president Artur Mas said the region was simply asking for its own money back.

Mas has said he wants the region to be able to raise and spend its own taxes, according to Spanish news site Expatica.com.

On Friday, the Catalan regional government gave the green light to a $6-billion hotel-casino complex near Barcelona in an attempt to boost tourism, Reuters reported.

Support for independence in the region now runs as high as 51 percent by some polls, the Guardian reports, the highest in years.

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