El departamento de justicia norteamericano lo tiene claro...

Pues, de la página 7 a la 11 explican un poco de historia de Catalunya:


...the early eighteenth century, after Catalonia backed the losing Hapsburg side in the War 
of Spanish Succession
...
General Francisco Franco established a centralized dictatorship that was determined once and for all to put an end to the Catalan problem. What followed was one of the darkest periods of Catalan 
history, during which Catalans endured repression of individual and collective cultural 
rights, such as the prohibition of the use of the Catalan language, the public denial of the 
Catalan identity and the punishment [of] cultural expression.
...
In June 2010, the Spanish Constitutional Court struck down several 
parts of the amended Statute of Autonomy, including those defining Catalonia as a nation 
and giving formal preference to the use of the Catalan language. The court’s decision 
sparked widespread nationalist demonstrations in Barcelona. 
...

Economic issues have long been a source of friction between Barcelona and 
Madrid.  Catalonia is one of Spain’s wealthiest regions, but it does not control its own 
taxes; instead, Catalonia’s tax revenue goes to the central government, which then remits 
what Catalan nationalists argue is a disproportionately small amount of funds.  The 
eurozone crisis has exacerbated disputes over this taxation arrangement.  The Partido 
Popular government of Prime Minister Mariano Rajoy blames Spain’s economic woes on 
free-spending regional governments; by contrast, Catalonia attributes its deficit to its 
inability to control its own finances.  In the wake of the nationalist rally in Barcelona on 
September 11, 2012, Prime Minister Rajoy rejected Catalan leader Artur Mas’s request 
for a new tax revenue distribution plan.
...

...nationalists still managed to capture the majority of seats in the Generalitat.

In January 2013, the Generalitat 

adopted a “Declaration of Sovereignty” proclaiming Catalonia’s right to determine its 

political future in a referendum to be held by 2014a move to which the Spanish 

government has expressed vehement opposition.