Instapundit recently linked to an article at the libertarian Reason magazine with a premise I found – considering the authors and the magazine – surprisingly dimwitted. No, a border wall is not necessarily morally equivalent to the Berlin Wall, or anywhere near it. Consider Hadrian’s Wall, or the Great Wall of China. Sometimes there are actual barbarians on the other side of it.

But this does motivate me to try to clarify my own thoughts about libertarianism and immigration. Is there, in fact, any libertarian defense of border and immigration controls?

Let’s dispose of a red herring first. The fact that immigration controls are enforced by a government is not dispositive for at least two reasons. One is that one may be a minarchist libertarian, holding that governments have a legitimate but small and rigidly constrained set of duties including national defense; to the extent that border and immigration controls are construed as national defense, there’s no problem in principle with them. That’s the easy case, which I’m going to ignore for the rest of this essay except to note that I think this is how the founders of the U.S. would have conceived the matter.

Even for anarcho-capitalists like myself, government enforcement of law may be regarded as a historical accident that in itself doesn’t tell us much about which laws arise from the natural rights of individuals. The question to be addressed here is whether any system of law founded on those natural rights could include border controls on a defined territory.

The first question on the way to answering that is what “natural right” could border controls possibly be a defense of? The obvious one is that they might be justified as a form of collective self-defense. If you’ve got a peaceful, prosperous libertopia going, you’d really prefer not to have a bunch of people who haven’t signed on to your social contract walking in. Because you’re likely to have to kill or expel a lot of them in self-defense, and who wants that aggravation? Better to keep them out in the first place, allowing in only those who are willing to contract. Or who are sponsored by a citizen who is willing to post a bond against their behavior for the first N years.

(I’m being vague about how the process of binding oneself to the libertopian social contract works because there are a couple of different theories about that. None of the differences among these theories is relevant to the present essay. I will note that under any of them, “libertopia enforces the law” would cash out to “insurance companies pay security agencies to do it because the alternative is profiting less on those crime-insurance premiums”.)

Generally speaking libertarians don’t have a problem with border controls when the people trying to cross them are organized invaders, or individual criminals. The problem case, related to why immigration has become a hot-button issue in today’s politics, is whether border controls that keep out peaceful immigrants protect any natural right of the libertopians.

Libertarians like to avoid making nebulous ethical claims about groups, so let’s reframe this. J. Random Foreigner shows up at the border of libertopia, claiming he wants to become a member in good standing. What policy should the insurance companies tell their security contractors to have in order to optimize the expected change in payout on their crime-insurance policies?

Notice how this helpfully concretizes the problem. Instead of having abstract arguments about rights, defense of the rights of libertopians is priced into the insurance company’s decisions by people with skin in the game. Notice also that this gives the insurance companies an incentive not only to keep out bad actors, but to let in good ones. Criminals are loss generators; people who genuinely want to join the libertopian social contract, and are capable of doing so, are profit generators.

Let’s start with some obvious extreme cases. The guy has MS-13 tattoos? Nope, nope, nope. Obvious high risk. The guy is wearing Amish plain clothing and has a Pennsylvania Dutch accent? Let him in – those people are famously law-abiding and we can always use good farmers. In both cases one could in the extreme be wrong; Amish guy could be a sociopath and MS-13 guy could have given up gang life. But no rational person would bet on this and the insurance company won’t if it wants to maximize its profits.

Let’s continue by disposing of some obvious objections. Will the insurance companies exclude black- or brown-skinned people? I don’t think so. And if you think so, you’re probably a racist I want nothing to do with.

Why do I say that? Remember, the insurance companies are trying to optimize the effect of immigration on their profits. If you believe that having a black or brown skin is a sufficiently reliable predictor of being a loss generator for the insurance companies to use it, there are only two possibilities. Either you are wrong, in which case you have an irrational fixation about race and should be deeply ashamed of yourself. Or you are right, in which case the entire objection to “racism” as a belief system pretty much vanishes. I think the former is much more likely.

On the other hand, screening for a minimum IQ threshold would make a lot of sense from what we know about the correlation between IQ, time preference, and criminality. Set at any reasonable level, almost all Ashkenazic Jews will pass that screen, while many Australian aborigines and sub-Saharan Africans will fail it. This looks like racism, but isn’t; the only ethical question here is how predictive your tests are of the qualities required for an individual to function as a libertopian.

(Which also disposes of the usual nonsense about cultural bias in IQ tests. Cultural bias is actually part of the point here; you want immigrants who can function, speak your language or at least learn it rapidly, assimilate. A bit of cultural bias in the tests might be a good thing, though I’d myself be inclined to try to tune it out.)

Since you probably don’t want a repeat of the Rotherham/Cologne/Malmo rape-gang atrocities, there are some combinations of age, religion and country of origin that should be a crash landing. Anyone you have good reason to suspect of believing infidel girls are fair game to be “taken with the right hand” (as the Koran puts it) should be turned away. Worst case there’ll be a rape or murder victim, best case somebody will have to shoot him.

The predicate for this isn’t as simple as “Muslim” or even “Muslim male”. The university-educated 40-something Persian engineer I used to have as a downstairs neighbor would have been a good bet; anyone aged 13 to 35 from the back county of Afghanistan or the Tribal Areas of Pakistan, on the other hand…

Now let’s talk about the subtler aspect of the screening problem, which our hypothetical tribesman is a good lead-in to. This is the part I didn’t understand until recently, and why I’m more sympathetic to immigration restrictionists than I used to be.

Libertopia has both tangible and intangible assets. The intangible ones include, for example, the intelligence and pro-social traits of its people. Another is its voluntary consensus about how things ought to be done – and (which is not quite the same thing) the social contract itself. If I am a member of the contract network of security professionals and arbitrators that enforce libertopia’s norms, I’m not going to think my job ends with defending the tangible assets of libertopians. In fact, I’d consider identifying and defending the intangible assets more important, because they’re more fragile.

Again, let’s concretize this. One of the intangible assets I benefit from as an American – and which I would expect libertopia to have – is that in my society, I can usually make handshake deals with strangers and expect them to be honored. I live in a context of what people who study this sort of thing call “high social trust”. (In part because I avoid the places in the U.S. where social trust levels are low.)

This is more important than anyone who has never lived outside a high-trust society really understands. In low-trust societies, you can’t count on anyone outside your family or tribe not to betray an agreement for short-term advantage. Large-scale cooperation is difficult. Rates of crime and violence are high, the law is unreliable, and at the extreme blood feuds are a common way of pursuing disputes.

The sociologist Robert Putnam is now (in)famous for noticing that diversity – whether it’s linguistic, ethno-racial, or religious – erodes social trust. This is why in “diverse” societies people tend to self-segregate into groups of like kind; they want to deal with neighbors whose behavior they can predict. But what Putnam found is that diversity does not merely erode trust across groups; it erodes trust within them as well.

If I’m a citizen of libertopia, one of the things I want defended with my crime-insurance premiums is the high trust level of my society.

This is why my position about immigration policy in the real world is different than it used to be. I started with the usual libertarian disposition in favor of open borders. I also started with – I’m now ashamed to admit – the usual Blue-Tribe presumption that opposition to unrestricted immigration is at best vulgar and plebeian, at worst narrow-minded if not actually racist.

I should have listened more and reflected the class prejudices of my birth SES less. I now understand that the core complaint of the anti-immigration Trump voters isn’t even about illegals low-balling them out of jobs, although that’s certainly a factor. It’s “I want to keep the high level of social trust I grew up with, and I see mass immigration – especially mass illegal immigration – eroding that.” They think the political elites of both parties, and corporations profit-taking in the labor market, are throwing away that intangible asset to plump up a bit more power and profit.

I now think that is a serious – and justified – complaint.

In the short term, the willful denial of this problem by our soi-disant “elites” is probably Donald Trump’s best hope for reelection in 2020. And no, I’m not excluding the booming economy; I think this matters more to his base, even if they have trouble articulating it. And I don’t think that priority is wrong.

In the longer term, what is to be done about it?

I think I’ve already shown that the contingent fact that real-world border controls would have to be enforced by a government is not really a bar to designing them. Americans made choices over generations to build the asset called “high social trust”; the fact that they must now, practically speaking, use government to defend it is no more problematic than are government-enforced laws against theft, rape, and murder. How we transition from the current system to libertopia is an orthogonally different question.

To begin with, I’d have the Border Patrol and ICE do what libertopians would do. Screen by individual merit and by culture of origin, deliberately excluding people from barbaric low-trust milieux, people who don’t speak English, people with seriously subnormal IQs.

Because I think I know what policies are ethically proper for libertopians to do to defend themselves, I think I know what is ethically proper for Americans to do. And it all has to begin with the premise that coming to the U.S. is not a right, it is a privilege you earn from the expectation that adding you will be good for the health and future of America.