The right does not refer specifically to being a colony. There are many examples of countries which seceded which were not a colony.

The Catalans still have a national day to remember how they were defeated by the Spanish armies and lost their institutions and laws. This will remind them at least yearly that they were once independent.

- https://en.wikipedia.org/wiki/National_Day_of_Catalonia

- https://en.wikipedia.org/wiki/Siege_of_Barcelona_(1713–1714)

And it is not like there are no secession movements in the USA:

- https://en.wikipedia.org/wiki/Texas_secession_movements

- https://en.wikipedia.org/wiki/Partition_and_secession_in_Cal...

Although I agree the case to be independent must be really strong in the USA for it to work and won't happen soon.

And see cases like Taiwan which are still in limbo.

In the end it is about acceptance by the international community which will decide what is a country and what not.

Catalans didn’t lose anything, they were part of the Kingdom of Aragon (a part of the Kingdom of Spain), and when Charles II died without heir, there was a civil war against two European families: Bourbon & Habsburg. Castile nobles chose Bourbon while Aragon ones chose Habsburg.

The war was not because of some “state rights” or whatever you’d like to say, it was a fight for the Spanish Crown between two European Royal Families. If Aragon nobles chose with such bad luck that they were in the losing side, that’s Human History.

I said they lost their laws and institutions as it is mentioned on the linked wiki page. It is a big deal to them as is clear how they present it in the museum of Catalonia in Barcelona and how big they remember this day every year. They want to be more in control of their own rules and destiny and that fight is still alive.

The question is if this is the majority or a loud minority. But without a proper referendum we will never know exactly. But how they vote in regional elections seem to be that most are more separatist.