And?
No taxation without representation. They opposed a regime imposing their will on them without allowing them any say.
Your grasp of US history is simplistic to say the least.
I don't trust any far right organisations in these kind of matters. If anything I assume their support is entirely to try and destabilise the EU.
It doesn't matter if a distinct people with their own language and culture are oppressed by an occupying power or fully represented in a democracy they are still entitled to self determination. Quite a few here some to believe that if a region/nation has it good why would they even want independence. That's completely besides the point, it's about freedom to determine your own path.