In 2015 the ZGBlog Open Immigration countered Prof. Hoppe's libertarian argument in favor of border controls, which centered - rightly, I think - on property rights; but recently I found a different argument to the same end by Ilana Mercer, called Wage Walls, not Wars. She reasons on the basis of culture.
Please read it for yourself, but I summarize her argument this way: the Non-Aggression Principle (NAP) is the bedrock of libertarianism, and nothing in it gives anyone the right to migrate. Further, "ordered liberty has a civilizational dimension, stripped of which the just-mentioned libertarian non-aggression principle... will crumble." She evidently endorses the view she attributes to "paleoconservatives" that "the libertarian non-aggression principle is peculiar to the West." Hmm.
The NAP is derived from the Self Ownership Axiom (SOA), which is undeniable, and holds that aggression - initiating force - is wrong. That's all it does. So morally, a human being can do anything at all, provided he doesn't aggress. It's the one and only valid restriction on human behavior, and it's integral to the SOA; since everyone is a self-owner, nobody may rightly force him to behave such and so and therefore he may not apply such force to others.
But otherwise, he's free to do anything. It's a liberating principle!
Ms Mercer alleges that the NAP does not give anyone a right to migrate. I reason that on the contrary, it does exactly that! Provided only that the migrant doesn't trespass on someone's owned property, he can go anywhere, for doing so does not initiate any force upon anyone. I think she has it upside down. Don't you?
What, though, about the "civilizational dimension" without which Ms Mercer thinks the NAP will crumble? And how about the assertion that the NAP has surfaced only in Western culture? A read of the recent ZGBlog Civilization may be useful.
Take the latter first. It's quite true that a systematic libertarian philosophy has developed only in "the West", and only since about 1850. However it had a healthy boost also in Russia at about that time too, and expressly anarchist ideas took root better there than in the literal West; take Tolstoy, for example. All of them fell short because those early thinkers felt the need of hyphens; -syndicalism, -communism (!), etc. Those qualifiers gutted anarchism of its essential nature, by inviting another form of rule. Nonetheless, in a very dark place candles were lit.
What, also, of more primitive societies? - what of Native Americans, indeed? They never proposed a formal libertarian society because their whole way of life was not far removed from an informal one anyway; they took any communal decisions by consensus, not by edict. A "chief" was a chairman, not a dictator. Anyone dissatisfied could readily leave the local group. I think Russell Means would have agreed. While the incoming Europeans brought a "civilizational dimension" those victims of genocide may well have figured that they could teach the palefaces a great deal about civilized behavior.
Certainly, I'd concede that some cultures, notably Islam, will resist ideas of liberty. Zero government societies will spread first through the English speaking world, then others, and probably last of all to those unfortunate, brainwashed, tightly controlled people. But otherwise, freedom is a fine fit for any human being. The alleged problem of want of a civilized culture is, IMHO, seriously overstated. The prequisite for a society with the NAP at its core is not that it become civilized, but that its members first learn the nature of freedom, then stop working for their rulers - religious or secular.
To that zero government society, immigrants will be welcome. If they come with archist baggage, they will find no use for it, for the structure of government will not exist. Harry Browne's superb, short story about the fictional, anarchist country of Rhinegold (Ctl-F that word in the .pdf) even invading soldiers were wholly frustrated when they found that few residents knew what "government" meant! (So they stole some cheese and moved on.)
That is why I don't see immigrants from anywhere posing a problem for the ZGS. It's rather probable that they will in any case be those from an archist society who are least satisfied in that environment, and so that they will be a positive influence from the moment of their arrival; but even if they come with intent to harm, they will find no opportunity to cause it. There will be no levers of power for them to grab, and if they resort to krime they will face a justice industry far more efficient than the government "justice" system they just left. The "crumbling" will not be of the NAP, but of their expectations that they can impose their will on a society of self-rulers.
Lastly, will immigrants from less enlightened cultures damage America if they come now, while the government era continues? - this may, after all, be a focus of Ilana Mercer's writings. Of that, I'm not sure; but in any case I have no interest in shoring up the present régime. I don't want to prolong its miserable life, but to end it. Even so, if (how?) a hundred million Islamic zealots moved here and took control, would the task of dislodging them be harder, or easier than at present? The existing top layer of government junkies is every bit as brainwashed, so I don't see a heap of difference. All that's needed, by the TOLFA method, is so to re-educate the rest of society that nobody will work for them. Then they will implode, whether wearing turbans or power suits.