Irish Republicanism

[Sic Semper Tyrannis]

Why are Leftists supportive of Irish Republicanism? The Irish are no longer oppressed in Northern Ireland.

Even if it was justified from some kind of pseudo-nationalist "national liberation" movement, would that not then justify the same movement on part of the Ulster-Scots?

[Remus Bleys]

Because many on the Left are influenced by the intentionally vague, populist line from the bolsheviks, that apparently, all nations had a god given right to self-determination.
Even if it is something as miniscule as Quebec, Scotland, or Ireland.
What they do not understand is that the more local bourgeoisie is still bourgeoisie, and is just as oppressive (albeit in different ways).
National Liberation is a dream, for the same reason Socialism in One Country is. All of these "liberated" nations essentially exchanged one imperialist backer for another. Capitalism and Imperialism are global systems, it is impossible to change that without a worldwide revolution which must be ruthlessly fought meter by bloody meter.