The Spanish prime minister Mariano Rahoy decisions to use force to suppress the
has given what the independence movement need it: an enemy to fight against. All the nations were formed against an enemy.
When you see police storming poll stations, you think at fascism, Franco and last resistance of Catalonia against Franco's dictatorship. These are powerfull images that can be used to rally people to Catalonia independence cause.
The intolerance brought the scourge of the civil war on Spain, and it seems that this lesson was not learned by Spaniards. They try to settle old scores even now.
Franco could be more lenient towards his political opponents and not build concentration camps to kill them.
Mariano Rahoy could be more lenient and not order police to use force against some people who voted.
He could let people vote and even encourage them to vote in order to win a majority.
Even if the referendum would be 100% for secession he could claim that is unconstitutional and refuse to acknowledge it.
What the Catalans would do? Take arms and face Spanish army?
If the Catalans would lead an armed revolt they would be the bad guy at TV, not the Spanish police.
Mariano Rahoy transformed a local problem: the Catalonian independence in a global problem: the right of people to assembly and express an opinion in Spain.
Maybe there are Catalans who didn't support independence, but seeing that their friends are beaten by police for voting, they change their opinion.
They were independence referendums in Scotland and in Canada and they didn't won the majority. Why was the Spanish government was afraid? That Catalonia will secede?
Czechoslovakia separated peacefully after '89, so even the Catalan's divorced they could have good relations with Spain, maintaining they economic ties. Not even now they don't have a border between these countries.
Yet while Czech republic and Slovakia shared a common destiny and never fought one another, the actual Spain was created by Franco with help of the army, similarly with what Tito did in Yugoslavia.
The advantage for Spain is that has common history for all its provinces since 1492 and a strong identity, but it had a civil war and unresolved disputes and it has strong local patriotism.
To spark a second civil war it needs an economic crisis or some other form of chronic discontent, intolerance and external support with weapons.
The government is intolerant, Catalonia has a busy harbour and can receive weapons from all over the world (Lybia is near) only the economy is recovering but youth unemployment is high.
Those who sow wind, reap storm.