Do Pandemics Strengthen the Case for Restricting Immigration? [updated with response to Jason Richwine]

Temporary quarantines and other targeted restrictions might be justified. But pandemics do not justify more general migration restrictions. Indeed, the latter often actually imperil health.


The rapid spread of the coronavirus pandemic around the world has led some to argue that it strengthens the case for imposing tight restrictions on immigration. Nationalist populists in Europe have begun to promote that idea. Here in the US, President Trump has endorsed a supporter's claim that coronavirus makes it more imperative than ever to build a wall on the southern border, even though the director of the Center for Disease Control indicates there is no evidence that would help curb the virus.

I'm an advocate of open borders. Still, I have long recognized that limiting the spread of a deadly disease can justify some restrictions on freedom of movement across international boundaries; I most recently made that point in my forthcoming book Free to Move (written before the coronavirus crisis began).

At the same time, protection against disease does not justify broader, more permanent migration restrictions. The latter actually imperil health more than they protect it.

I. Quarantines as a Justifiable Constraint on International Freedom of Movement

As I envision it, the argument for open borders is not a case for an absolute right, but one for a strong presumption of freedom to migrate across international boundaries, similar to the presumption of internal freedom of movement in liberal democratic societies. Similar views have been advanced by leading defenders of open borders, such as Bryan Caplan, Joseph Carens, and Jason Brennan, among others.

The case for open borders rests on the points that migration restrictions are severe constraints on liberty, that they doom millions of people to lives of poverty and oppression, and that they do so on the basis of morally arbitrary characteristics, such as who their parents were and where they were born. Migration restrictions also restrict the freedom of natives, as well as migrants, and  block the production of enormous wealth that could otherwise have benefited both groups. Finally, most standard arguments for immigration restrictions would - if applied consistently - justify severe restrictions on domestic freedom of movement (and other liberties of native-born citizens), as well. That is particularly true of the theory that governments can justifiably restrict immigration because they have the same right to exclude people from "their" land as private property owners have to restrict entry into their homes. Yet few restrictionists are willing to bite this bullet and apply their arguments consistently to both the domestic and international cases.

But there are cases where these points may not apply or are overridden by other considerations, such as a great evil that can only be prevented by limiting migration. Impeding the spread of a deadly disease qualifies as such.

Saving life is is a major moral imperative. And, at least in some cases, a quarantine may be the only way to achieve that goal in the face of the spread of a deadly disease. This differentiates quarantines from most other arguments for migration restrictions, the vast bulk of which address threats that are overblown, can be addressed by less draconian means than exclusion, or both.

Second, unlike most rationales for restricting migration, this is one widely accepted as a justification for restricting internal freedom of movement, as well. Indeed, the most draconian restrictions on movement enacted by any liberal democracy during the coronavirus crisis so far is Italy's lockdown of their entire population - whose main effect is to prevent Italian citizens from moving around their own country.

If fairly applied, quarantines need not discriminate on the basis of place of birth, parentage or any other morally arbitrary characteristic. They can be imposed on anyone - migrant or native - who poses a sufficiently grave threat of spreading the disease in question.

Finally, unlike conventional migration restrictions, quarantines generally need not and do not last more than a few weeks or months. In most cases, this is a far lesser imposition on would-be migrants than conventional migration restrictions, which routinely exclude people indefinitely, condemning many to a lifetime of poverty or oppression.  For most potential migrants to the US and other wealthy nations, there is no "line" they can join to have a real chance of getting in legally within their lifetimes. Not so if the only barrier to entry is a quarantine that will be lifted as soon as the crisis at hand has passed. The short-term nature of quarantines also minimizes the economic harm they cause.

The fact that migration-limiting quarantines are theoretically defensible doesn't mean that all actual policies of this type are justifiable. Here, as elsewhere, real-world governments often fall short of theoretical ideals. Trump's recently announced Europe travel ban, for example, seems unlikely to actually impede the spread of coronavirus. Similarly, it is not clear that Italy's draconian restrictions on freedom of movement are actually effective; at the very least, considerable evidence suggests they are much less so than South Korea's far less coercive approach.

Still,  it is significant that quarantines can be justified on grounds that differentiate them from more conventional migration restrictions. Few if any of the latter have a comparably strong case. Whether quarantines are defensible in a given situation depends greatly on the nature of the disease in question - an issue I must leave to those with expertise on epidemiology and public health.

II. Why Conventional Migration Restrictions are Often a Menace to Health.

By contrast, standard long-term migration restrictions not only cause greater harm than quarantines, but also often are a menace to health. Perhaps the biggest reason is that they block the production of enormous amounts of wealth by preventing people from moving to places where they would be more productive. A world of free migration would be vastly wealthier than the status quo.

One of the better-established findings of social science is that wealthier societies are also healthier ones. We are healthier and longer-lived than our ancestors primarily because we are much wealthier than they were.  Wealth enables us to produce more medical innovations, and allows us to devote more resources to health care. As a consequence, wealthier nations generally also do much better in minimizing the loss of life caused by epidemics.  Migration restrictions make the world much poorer than it would be otherwise, and thereby also slow the pace of improvement in health.

In the United States, migration restrictions also imperil health because immigrants  and their children are disproportionately represented among doctors and scientists. Many of the doctors treating coronavirus victims and the scientists working on producing a vaccine are likely to be immigrants. We would be in far worse danger without them.

Perhaps the doctors and scientists in question could have made similar contributions to health care if they had stayed in their countries of origin. But in most cases, that isn't true. The US and other advanced nations offer far better opportunities for medical training and scientific research than the often dysfunctional nations from which migrants hail. Scientists, like many other people, are more productive in nations with better institutions.

It can also be argued that the US should let in migrants who who seem likely to become doctors or scientists, but keep out most others. This, however, assumes that government can do a good job allocating labor, and predicting which types of workers will make useful contributions and where. That assumption is unlikely to be true; if it were sound, the Soviet Union might have been a great economic success story. Moreover, immigrants who are not scientists or doctors themselves can nonetheless increase the productivity of those who are, by increasing the overall wealth of the economy. As already noted, additional wealth tends to translate into improved health.

Immigration restrictions also imperil health in two more direct ways, both of which have special relevance to the coronavirus situation. First, our immigration restrictions have created a large undocumented population. If members of this group come down with the coronavirus (or some other contagious disease), they may be reluctant to come in for testing and treatment for fear that revealing themselves to the authorities will result in detention or deportation. That could imperil not only the undocumented themselves, but others who come into contact with them.

For that reason, a recent statement by experts in public health and health law urges that health care facilities addressing coronavirus cases should be immigration enforcement-free zones:

Healthcare facilities must be immigration enforcement-free zones so that immigration status does not prevent a person from seeking care. The COVID-19 response should not be linked to immigration enforcement in any manner. ​It will undermine individual and collective health if individuals do not feel safe to utilize care and respond to inquiries from public health officials, for example during contact tracing.​​

I worry, however, that the federal government may not adopt this sensible policy. Even if they do, official assurances may not be perceived as credible by migrants who have good reason to be wary of immigration enforcers, who have a history of using deceptive tactics.

Second, immigration enforcement has created a system where the federal government detains thousands of migrants in facilities that often feature poor hygiene and medical care. That increases the risk that coronavirus (and other diseases) might spread rapidly among the detainees, and potentially also imperil the surrounding population.

In sum, there is good reason to believe that migration-restricting quarantines are justifiable - at least in some cases. But that justification does not apply to more conventional long-term migration restrictions.

UPDATE: Jason Richwine of National Review responds to this post, as follows:

Libertarians who take Somin's position — that almost everyone should be allowed to enter, but not terrorists or disease-carriers — need to answer a follow-up question: How do they intend to enforce the restrictions? Surely not with a border wall, which is anathema to immigration boosters. How about expanding the Border Patrol? ICE raids? A nationwide ban on sanctuary jurisdictions? To my knowledge, they oppose all of these tools for immigration enforcement.

In order to place meaningful restrictions on who enters our country, we need to have mechanisms in place to ensure that the rules are being followed. That's true for any immigration policy short of open borders. Whether the law bars nearly every foreigner or just a handful of bad actors, enforcement is required to make it happen. And such an enforcement regime cannot instantly materialize in a crisis — it requires an existing set of institutions and procedures developed over time.

As noted in my post, a pandemic can justify not only restrictions on international freedom of movement, but also even some constraints on internal mobility. It does not follow that we must have a large-scale ongoing regime for constraining internal freedom of movement. We can instead have special rules that apply only during an appropriate crisis, and resources to implement them that are available in reserve. When it comes to terrorists and similar bad actors, we can use law enforcement to track international terrorists, much as it does with domestic ones, without a general regime of constraining internal movement.

These sorts of policies do require resources. But nothing like the massive enforcement regime that currently exists to keep out the far larger number of potential migrants who wish to enter during normal times in search of greater freedom and opportunity.

Indeed, the extra wealth generated by increased migration and by reductions in conventional "border security" spending can easily be used to fund a more limited enforcement capacity focused on unusual crises, such as pandemics. And, as noted above, "ordinary" border enforcement has side effects that actually make combatting pandemics more difficult.

NEXT: Mormons Cancel Church

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  1. Why would you apply an exclusionary rule "consistently" to two entirely different groups? Native and naturalized countrymen are ours — people we share a degree of common cause and some amount of mutual obligation towards. Foreign nationals are distinctly not ours — we share little to no common cause with them and have little to no mutual obligation — certainly much less than to our own countrymen. The argument that "consistency" requires treating the two groups exactly the same ignores the very clear actuality that they are not the same.

    Why isn't this blindingly obvious? What sort of person has difficulty understanding something like this?

    And even if you disagree and you think there's zero difference, by what right do you impose such a view and all the consequences of that choice on everyone around you?

    Imagine living in an apartment complex and inviting the homeless to share the common spaces whenever they want. The other residents will become your enemies immediately, and with good reason. Imagine continuing to do it, day after day, regardless of the other residents saying no over and over, every way they possibly can. Do you imagine that ends peacefully? Do you imagine the person inviting the homeless to live in the courtyard and the common rooms is the good guy, despite all the rest of the residents disagreeing? I don't think you do.

    1. Also, let me reply to an argument in advance. Someone will say "immigrants are not the same as the homeless".

      If you don't control who you let in, they absolutely are the same. Imagine you've opened your common space to everyone. A PhD scientist shows up. A concert cellist with her husband and young son. A plumber. You have enjoyable conversations and everything is grand. Open borders are a big success!

      Then 2 homeless people show up. Then a third homeless person. What happens to your happy little group? You can't exclude anyone because that's the key mistake you've made from the very beginning. Do they all hang out together?

      The family leaves first. Now there's more room. A fourth homeless person shows up. The plumber and the PhD scientist leave. Maybe they join the family in a new place. You know that they're going to insist on in their new place? You do know. They'll want a border. Or a wall. Some way to keep the homeless out.

      What became of your common space with no borders and no exclusions?

      1. How about the argument that you're a bigoted asshole who thinks all immigrants are more likely to be incapable of paying any bills and therefore a drain on our illustrious society, rather than people who have the ability to contribute positively to America?

        The bigoted asshole diagnosis extends to your claim that we have "little to no common cause" with foreign nationals. As though the US is the only "Western Civilization" on the planet, and our ideals are incomprehensible to the rest of the world.

        People who wish to move here clearly have a common cause with those of us already here, or they WOULD NOT WANT TO MOVE HERE. Same reason I don't want to move to Iran.

        Go back to your white nationalist rally.

        1. Ad hominems abound!

          Immigration may or may not be beneficial. Illegal immigration is definitely detrimental to the rule of law (remember that?). And the citizens have a right to determine immigration policy through their representatives. Want to change things, change the system.

          Those ad hominems must have occurred to you when you glanced in the mirror.

        2. You accuse him of being a bigot yet you are the one who wants to ignore the individual and treat the entire group as though they were the same. I’ve had the pleasure to work with many people from other countries and cultures and they run the gamut from those who appreciate what we have and would like to join us to those who dislike Americans and are just here to make money. On a case-by-case basis, it may make sense to allow each individual into our country, but we should make those decisions and not close our eyes and just let THEM in or keep THEM out.

        3. People want to come here because our country is wealthy, not because they have common cause with those of us already here. Central American migrants walk an extra 1200 miles to cross Mexico to reach the United States, even though they have much more common cause with Mexico in regard to culture and language.

        4. I should also point out that the difference is even more stark in Europe. Islamic migrants head for Europe instead of other Muslim majority countries, even though they have very little in common with Europe's language and culture, and overall have diametrically opposed values on issues like feminism and gay rights. They go there simply because Europe offers more financial benefits.

        5. That you focus on what immigrants have to contribute economically, and not whether or not the citizens of the receiving nation actually want those people to be present, is proof that you are no libertarian. You should consider self-deportation to the EU; they never cared about freedom of association to begin with.

          Your naivete is sad. There is no other nation like the US. Our ideals are actually extremely incomprehensible to the rest of the world. Notice the lack of 1A or 2A anywhere else in the world. You know who is actually most similar to America now? Japan, because we modeled their Constitution after ours.

          Coming to the US for economic opportunity is not a common cause. If you want a mercenary nation, go make your own. But don't shit up America in the process with your social experimentation. My standard of living could never be anywhere near as important as making sure we maintain a culture that not only preserves the Constitution and BoR, but aggressively fights back against the many hits out rights have taken over the past hundred years. It is pathetic that you and many others regularly misconstrue this desire as white nationalism. Tell that to all the "black and brown bodies" who feel the same exact way about their rights and the erosion of the American body politic. I cannot help but wonder if you have ulterior motives because it is suspicious how you characterize a restoration of natural rights as white nationalism. You could at least try to be nuanced, yet choose not to. Why is that?

          1. "Japan, because we modeled their Constitution after ours."

            More accurately, our government modeled their Constitution after the parts of our Constitution our government didn't dislike. Which is why Japan doesn't have a 2nd amendment, for instance.

            1. Well there was another reason we didn’t want the Japanese armed at the time, though that doesn’t mean your point wasn’t also true.

          2. The push to continue our de facto open borders policy is not driven primarily by naivete. The motives are hardly ulterior, though, as progressives and neoliberals alike openly celebrate an anticipated permanent electoral majority, achieved strictly by means of demographic displacement, toward the openly stated end of abolishing the very ideals of liberty and decentralized self-government that you are referencing. The globalists and the statists know that full well that our de facto open borders policy will have this result and that's the whole point. And since this aligns with the interests of big business in keeping wages down, preventing competition, and achieving artificial economies of scale through centralizing big government regulation, it becomes very difficult to pass reforms to immigration policy that are overwhelmingly favored by and are overwhelmingly in the best interests of Americans.

        6. Name calling shows you are too dumb to form any sort of meaningful argument.

          Homeless people want to live wherever they can get something for free. If you don't control entry, you end up with a giant homeless camp. No one else will want to live there. I already explained this.

          1. Again with the immigrants=homeless bullshit.

            The only thing that you've 'explained' is that you're xenophobic, and should not be taken seriously.

            Just put on your white hood and be done with it, Ben.

            1. It's a pity that you are so mentally limited and unable to understand, even with a clear explanation.

              It's not that all immigrants are homeless or criminals. If even a small number of criminals and homeless are allowed, they take over the space and everyone else leaves.

              This was clearly explained and everyone except you understands.

              1. It's cute that you think you can denigrate immigrants repeatedly, as the entire substance of your post, and then try to claim that you didn't actually mean what you wrote.

                Many Americans are criminals or homeless, yet you don't have a word to say about them. Just those nasty immigrants come to ruin your country.

                1. The world must be very scary for someone like you, unable to read a few short paragraphs with uncomplicated sentences and understand. No one else seems to be having any difficulty.

                  1. That’s because it’s easy to read your claim as a cover for bigotry.

                    Imagine you’re actually a bigot, but know that bigotry isn’t well received by the commentariat. How do you structure your claim so that you get your desired result (or close to it) in such a way that you can convince non-bigots who haven’t thought about it? You make the argument you did.

                    But if you’re not a bigot you would also make that same argument, because judging people as individuals is the only moral act, while judging people as a group is inherently bigoted because it reduces the individual to only a single (or few) characteristics rather than evaluating them as a whole.

                    Bigots will always think you’re making the bigoted argument, just that you’re the wrong sort of bigot.

                    Take my wife for example: mixed African and Pacific Islander immigrant, who is against open borders but in favor of a wide immigration policy. Her view is that anyone who wants to be part of the American Experiment should come here - they’re self selecting to share the broad American values, while people who merely want to work here should also be allowed in, like the Vaquero Program mid century.

                    But how can you tell them apart? One way is to prohibit the use of all social services and safety nets for an extended period, such as 5 or 10 years (we could figure out where that point is, but I don’t know it now), so that people who merely want to be here for the benefits no longer have an incentive to do so, while those who want to come for temporary work and those who want to join the American experiment can still come.

                    1. Didn’t get past the name calling in the first line.

                      You guys sure are bad at this.

      2. It is one thing for a person to offer to 'share' his/her apartment with a homeless person when the person who invites the homeless is responsible for that homeless person. It is totally different when this homeless person is now living off those around him/her and not paying his or her own way.
        The politics of today in certain political parties(s) is to give to the immigrants full rights to entitlement and even voting as citizens have. I am for immigration but I want immigration that will benefit THIS nation and will give the immigrant a chance to excel if the immigrant has the ability. But I am not in favor of taking in people from other nations that from the start has to live off the taxpayers of this land.
        I would be for a person or a group of people to sponsor an immigrant or family but that person would be fully responsible for that immigrant or family even for any criminal activity that the immigrant or family does. That responsibility would continue until that immigrant or family is established as self-supporting and law abiding. Then then after certain time the responsibility for the immigrant or family could be lifted and the individual or family would be on its own.
        But to open the border and for just anyone or every body to have free access to this United States without any restrictions, NEVER.

  2. The simplest counter-argument to Professor Somin is to say that open borders is the wrong policy approach. And it is.

    The truth is, we do not want every immigrant who wishes to come here. Particularly those without skills we need, or those who would become a public charge. No thanks. Been there, done that.

    The US should adopt a merit based immigration program, and let 5 million people a year come here annually who have the critical skills we want: mathematics, physics, biology, chemistry, engineering, etc. We do not need landscapers, bus boys, or lawyers (sorry Professor). These high skilled future Americans are precisely the people we want here to build the America of tomorrow.

  3. I'm an advocate of open borders.

    The rest is just sophistry.

    1. Translation: I am unable to engage with his argument in any substantive way.

  4. I think the problem isn't so much when you argue that open borders is a good idea, or moral. (Though I'll still disagree to some extent.)

    It's when you move to arguing that it's constitutionally required. To paraphrase, "The Constitution does not enact Rawls' "A Theory of Justice"." You can think we ought to have open borders all you like, that doesn't make them legally mandated by the Constitution we actually have.

    And, when it comes to libertarian theory, you're just completely blowing off the complexities of the early theorizing dating to before the long march through the institutions overtook so many libertarian sites.

    The key phrase here is "path dependence". Sure, you can be for open border, and for ending the welfare state, but it matters a lot which you do first.

    We are a welfare state. We give free stuff to people. No, not free, paid for by other people who aren't given a choice about whether to foot the bill. We set a minimum standard of living people aren't permitted to fall below (if they don't want to) that is higher than the standard of living across most of the world.

    That makes us a poor people magnet. Sure, productive people want to move here, to enjoy being productive. Poor people want to move here, too, to enjoy our idea of poverty, which is a fair degree of prosperity by the standards of much of the world. And there are a lot more poor people in the world.

    Open borders is suicidal for a welfare society in a world where there is poverty. It's doubly, trebly suicidal for a welfare society next to a third world country with an ongoing civil war.

    This isn't daisies and unicorn farts economics. It's lifeboat economics. Convince people that liberty demands suicide, and they won't nobly drown, they'll reject liberty.

    Please, stop trying to tie liberty to suicidal policies.

  5. Putting aside the facile arguments put forth here, Does professor so in ever have to contend with the fact that if his open borders policy obtains (or the US even keeps on its current course of porous borders) US society will look decisively UNlibertarian in just. About every other way? I mean just look at voting patterns. It’s not like the welfare state or voting rights won’t be extended to newcomers even if they are illegal.

    And despite Jason Cavanaugh’s screeching about racism above, few people in the world have cultural affinity for western civilization. It is not clear that, when this country is inundated with 3rd worlders, the Anglo American legal system will survive, especially free speech

    The country will be less harmonious and super unpleasant.
    But so in never has to answer for this because he can just screech about racism. You’d think someone from the Soviet union would know the dangers of taking an absolutist theory too far and ignoring pragmatic real world consequences

  6. Isn't the experience of Western Samoa and American Samoa during the Spanish Flu epidemic instructive?

    Western Samoa let anyone in and was hit hard. American Samoa barred ships and instituted a quarantine and not one person died form the flu.

  7. South Korea, where a competent government has already tested hundreds of thousands, has a good reason to exclude lazy, scrofulous, untested Americans.

    1. They sure do, we can start with withdrawing our 40,000 troops there.

      1. Considering that for a long time now it’s only because of American belligerence that North Korea has become such a threat . . .

        1. So we are agreed?

        2. I've never quite understood this conviction that nobody has agency in the world except us.

          1. Many people really do want to be their brothers keeper......

            Fairy tales are usually morality stories, after all.

          2. The operative word with South Korea and the United States is "hegemony".

    2. Oh wow, you actually called SK's government competent. My Korean friends are going to die of laughter when I tell them this later.

      1. They’re getting it done, we’re not.

        Still no one refuting my point, just the usual drive by conservative irrelevancies.

        1. "refuting my point"

          Whats to "refute"? I think we all agree, Korea is fully justified in keeping Americans out. Or anyone.

          " scrofulous"

          Had to look up.

          You have a lovely view of your fellow Americans.

          1. Just the view anyone outside of the U.S. would reasonably have about us, given the current situation and our "leadership".

  8. So, so, so much to comment on so I wil just make one

    "Trump's recently announced Europe travel ban, for example, seems unlikely to actually impede the spread of coronavirus."

    Lawyers ought not to practice medicine.

    "But Anthony Fauci, the head of the U.S. National Institutes of Allergy and Infectious Diseases, and a leading advisor to the Trump administration on COVID-19, defended the new European travel restrictions Thursday during a hearing on Capitol Hill.

    "If you look at the numbers," he said, "it's very clear that 70% of the new infections in the world are coming from that region — from Europe." European infections are seeding other regions, Fauci said, adding, "Second thing: Of the 35 or more [U.S.] states that have infections, 30 of them now, most recently, have gotten them from a travel-related case from that region. So it was pretty compelling that we needed to turn off the source from that region."

    He also says the China ban was helpful, though Somin's fellow open boarder-ers opposed it.

    [yes, you can find European experts on the other side]

    Open boaders and "free" trade is causing a depression and killing us. Good work.

    1. There's a saying about barn doors and horses that would seem relevant here.

      Also about cherry picking your authorities even as you appeal to authority.

      1. "GENEVA (AP) — World Health Organization chief says Europe now the epicenter of the world’s coronavirus pandemic." 24 minutes ago

        1. I thought lawyers ought not to practice medicine, Bob.

          1. Correct.

            How am I doing that? Citing the leading US authority and the head of the WHO? I made no statements of my own at all.

            1. Oh, you were offering that to prove the matter you asserted? Nope - nothing in the WHO quote says anything about closing borders.

              Pretty sure the pandemic bit means that'd be useless.

              1. Why are Mexico and Canada considering it then?

                If 100 people are infected in the US and then you let in 100 infected Europeans, you have increased your risk of infecting others in the US, correct?

      2. If you don't close the barn door, the horses will eat all the cherries before they're picked.

  9. "A world of free migration would be vastly wealthier than the status quo."
    Pure fantasy.

    1. Folks like Somin literally draw from scifi/fantasy movies in constructing their beliefs, while ignoring human history and the real world.

      1. No, Somin is right. A world of free immigration would be vastly wealthier, but only if paired with the other key components of US growth during our active immigration period (~1700-1900), when we only excluded the sick and destitute, and provided no compulsory subsidies for the poor, so that those who refused to be productive starved themselves out of the gene pool (ignoring the various racial immigrations bans i.e. China which should not be repeated).

        But that would essentially turn the world into a US style hegemony, with US style contract rights and civil liberties, and would be a much larger change than merely opening our borders.

  10. I'm not sure I've ever seen a collection of comments here having less to do with the original post. But you guys be you.

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