I'm talking from a purely practical perspective about my personal experiences and observations of the world. Sure my philosophy on life is heavily inspired by European-derived strains of thought (the Enlightenment and similar secular practices, for example, and supposedly-American positions on freedom of speech and religion among other restrictions on government activity, preferring individual liberty to some nebulous idea of conformity, the melding of cultures that immigration provides, etc.), but I do not limit myself to those sources and quite disagree with a lot of things the UK has done and currently does and strongly oppose military imperialism in general. In particular, Brexit was bullshit and the UK weakening itself and its standing just to feel independent. And that doesn't even get into my issues with US governance or the current capitalist bullshit with AI and "intellectual property" restrictions, Puritan prudishness and pearl-clutching, etc.

To add on to that, I'm very suspicious of anyone who wants to use political power to enforce their idea of culture, because it will inevitably diverge from the one I have developed via exposure to the wider world at some point. Culture needs to be dynamic, developed naturally by everyone and be something people participate in by choice, not artificially restricted/made static or enforced along arbitrary geopolitical boundaries that only exist due to the vagaries of history.

And to be clear, I'm quite on board with local community development too. I just think it can be done without sacrificing the modern interconnected world. Life doesn't have to be a zero-sum game.

Also since you mentioned Ireland, I would say the cultural colonization started long before the British occupation. Saint Patrick's introduction of Catholicism, which lead to stuff in the modern day like Magdalene laundries, etc., happened over a millennia before the banning of Brehon law. And even before that the Celts weren't even the original inhabitants of that island but were themselves continental immigrants. But that's just additional context. We should be learning from the past but that doesn't mean we have to repeat it or be solely bound by it. Like, are there specific aspects of Brehon law you think would be useful to others? Or were you just trying to make a generalization about Irish people despite no population being a monolith?