Millions died over those lines being crossed. They're immaterial, but they're not imaginary.
i think this is both i) too strong wrt to a border’s justification, which is at least partly discursive and conventional (like, it’s not a fact about the natural world); and ii) too weak wrt it’s real world consequences, which are clearly material.
Ultimately and in the abstract, is a political entity sovereign over a territory in its right to deny entry to people for whatever reasons ? I don't think I've often heard that clarified by those opposing nationalist arguments, the left in particular struggle with that.
left deontological:
1. In perfect conditions, everyone would agree to not live in a society subject to a voluntarist/absolutist state
2. In non-voluntarist/absolutist states, like constitutional democracies, all policy is subject to change based on the expressions of the will of the governed (or something like this, this is a really mangled phrase)
3. In constitutional democracies, states can’t affect policy -immigration or otherwise- for whatever reason.
Left consequentialist:
1. Nativist attitudes and policies create Pareto inefficient outcomes
2. We should optimize Pareto efficient outcomes (or whatever your favorite way of measuring utility is)
3. Nativist attitudes and policies should be avoided
neoliberal answer:
1. If capital is allowed to move freely across national boundaries, then labor should too
2. Capital is currently allowed to move freely across national boundaries
3. Labor should be allowed to move freely across national boundaries
Additionally, you can argue negatively, e.g., if the nationalist’s argument at any point relies on something like national/ethnic/racial naturalism (‘the nation’ is a simple fact of the natural world and exerts some kind of mind-independent causal influence) then it’s easily countered by just denying the premise
spoiler (click to show/hide)
the real answer here is: states are bad —> we shouldn’t have any
Likewise, the net effect on the economy is really hard to tease out empirically but the whole "costs millions of jobs" rhetoric is transparently silly.
Last time I looked into this the general consensus was that low skill labor slightly depresses wages in the target industry and was an overall slight net positive in the economy at large, and that’s with factoring in consumption of public services. And that’s just short term.
