Open Borders: The Case Against

Why open borders is a disastrous idea. (A book review.)

In this blog post I address the case for open borders, as put forward in the book Open Borders: The science and ethics of immigration.

This is a new book by Bryan Caplan and Zach Weinersmith, in the unique genre of graphic non-fiction. I am a big fan of both authors, and have read a large amount of their work. Both are brilliant thinkers with unique talents that have put their forces together to collaborate in making this completely new type of book, and the format works. It presents the ideas clearly and entertainingly, and I highly recommend it.

I strongly disagree with the opinion put forward in it though, and I will go through this in the following.

Scale of immigration

As a strong supporter of individual freedom and liberty, I find that the authors make a very strong case for the pros of open borders. There is no denying that allowing immigration could potentially help countless people who are given an unfair lot in life determined by their place of birth. This argument, like others, is very well described in the book.

However, I think that they do not deal with the extreme scope of potential immigration. The world contains a large number of poor people, who are strongly incentivized to immigrate if this can mean higher earnings and quality of life. The book mentions the extreme lengths that people go to in order to gain entry to the US:

And this is for illegal immigration. Imagine if immigration comes with full rights and all it costs is a plane ticket.

Historically we have seen that if there is open immigration, very large proportions of the population may immigrate. For example “Census figures show an Irish population of 8.2 million in 1841, 6.6 million a decade later, and only 4.7 million in 1891. It is estimated that as many as 4.5 million Irish arrived in America between 1820 and 1930.” (cite)

This shows that it is not unrealistic that half of the population of a region will want to immigrate, as long as there are good opportunities for them.

The region of Sub-Saharan Africa is especially important, since there are many poor people and because the population is projected to grow enormously over the next century:

If we make some guesses, and say that for example ⅓ of sub-Saharan Africans would want to emigrate, along with 1/10 of those from the rest of the world. These numbers are justified on the basis that large differences in living standards between host and target country are a primary, if not the primary motivating factor driving migration. They are based on the assumption that opportunities keep being good in the US. (If this is not the case, of course fewer immigrants will want to come, but then the open border policy that we are discussing has failed.) Modeling the projected world population growth together with these guesstimates of immigration, the population of the US in 2100 would have a composition of something like this:

I could stop the review here. It is blatantly obvious that such an extreme demographic transition to different populations with highly different characteristics would transform the country in countless detrimental ways. But let’s go on.

They even claim that US could keep the welfare state:

Given that most of the world’s population lives on less than $5 a day, most of them could thus get a large economic advantage just from the welfare they can get in the US.

The book supports immigration by pointing to the fact that immigrants in the US perform well on a large number of measures such as overall fiscal effects, crime, etc. But of course the current immigrants in the US are extremely selective and unrepresentative. And you cannot conclude anything about the whole group by looking at a highly selected subset, just like you cannot make conclusions about a whole school by looking at just the Valedictorians.

Here is a graph from Denmark showing that non-western immigrants are a net drain at all ages:

Cultural, political and societal development

The book puts forward the idea of magic culture:

Of course, culture is not a magic element that makes newcomers quickly and completely acquire the culture of their new homeland. In fact, culture is sticky and cultural differences persist over centuries. There is a good description of this in American Nations and Albion’s Seed, and a good summary can be found in this post. The immigrants from Europe tended to settle in different regions depending on their origin; they carried their culture with them, and these regional culture differences are still apparent centuries later.

It is obvious that a correct model of the development of a nation with immigration involves cultural / political pull in both directions. Smaller groups will get pulled more, and thus to some degree acquire culture by immersion, but larger groups will also pull in the other direction and change the politics and culture of their new home. The culture of immigrants changes to some degree, but the change is far from total, and strong cultural differences will last. And immigrant groups of enormous size will feel less of an assimilatory pull.

A related question is the political opinions of the immigrants. With open borders, the vast majority of immigrants will be low-skilled, since most of the world population is low skilled. And low-skilled immigrants on average tend to have political ideas that are detrimental to a productive society, as is also mentioned in the book:

If vast numbers of immigrants come to the US from societies in which there is overwhelming support for government regulation and spending, and against free speech, they are going to vote for those policies. Going by the pie chart of the population composition shown earlier, this will mean that such policies will indeed be enacted. But even a lower number of immigrants, say 50–100 million, would still have an enormous effect on policy. I assume I don’t need to present an argument here that exceedingly low levels of economic freedom is bad for the economy. Another perspective to see it from is to look at the effects of the policies voted for in the countries in Africa where many of the migrants would come from. It’s easy to see that they are extremely detrimental to well-functioning societies. Caplan himself sees things the same way:

The book itself also describes this problem expertly:

So which defense does the book put forward against this problem?

These arguments are not very persuasive when we are dealing with the enormous numbers of immigrants open borders would entail. Sure, 27% and 48% are lower than 72%. But 27% of a huge number is also a huge number. And the objection that the government doesn’t pay much attention to these voters is already doubtful, but if there is a voter bloc of hundreds of millions of people you can bet they will pay attention.

I haven’t been able to find much data about the views of second-generation immigrants. It is an important claim that they stop supporting things like government regulation and spending to a higher degree than the native population, and it is a claim which I am very skeptical of. What I do know is that in Denmark, support for making religious criticism illegal is even higher in second-generation immigrants, and that second generation immigrants commit more crime on average compared to first generation immigrants. Also, as discussed above, even if we accept that such political assimilation is extremely strong in the current society, we can’t be confident that this would still be the case if the immigrant population numbered in the hundreds of millions.

Immigration obviously also has consequences for society other than those enacted by the voting. For example, in Malmö there have been over 100 targeted explosive attacks so far this year, compared to a base-level of about 0 in cities without a large amount of recent immigration. Most of those convicted of rape or attempted rape in Sweden over the last 5 years are foreign born. This means that the number of rapes in Sweden could’ve been less than half of what it is today if it wasn’t for immigration. For some immigrant groups in Denmark, more than one in five are convicted of a felony each yearThis analysis I made shows that Germany would have had a very strong decrease in crime over the last 15 years if it wasn’t for recent immigration. All these numbers show that the problems with immigration is already very large for Scandinavia, with around 5–10% of their current population being recent immigrants from Africa and the Middle East. But they would obviously be vastly larger if we imagine an immigrant population in the hundreds of millions. It should also be noted that the detrimental effects of these things go over and above what is easily measurable, such as in government expenses. A society with widespread fear of violent crime, rape and bombings is a less open and joyous society. To the degree the book addresses these issues, it focuses on the current immigrant population in the US. But as discussed earlier, this approach is not applicable at all, since the current immigration population in the US is highly selected, and looks completely different from what the immigrant population with open borders would look like.

Philosophical arguments

Philosophical arguments that “prove” that open borders are good don’t carry much weight with me. Either borders are a net good or a net bad overall, and attempts to prove otherwise with analogies or Kantian-ish arguments invariably means that part of the picture is excluded.

In the book they feature Michael Huemer, who is a good philosopher and has a great blog at But the argument he presents in the book is exactly an example of an analogy that is not an accurate picture of the real situation:

In this analogy, the problem is not that Marvin is not allowed to move into the local marketplace and live there. The problem is that he is not allowed to buy bread from the marketplace. But this is a question of free markets, not open borders. All such hypotheticals are invariably limited, and there is no alternative to considering the full, real situation.

Keyhole solutions

In chapter 6, they discuss changes to the immigration system that are less radical than full-on open borders, but would still be an improvement over the current state.

One of their suggestions is to allow free immigration, but restrict immigrants eligibility for government services. I find this idea unpersuasive. While it will reduce the burden on the public finances, there will still be problems with crime. The problem with crime will likely be worse, since without any sort of government support, it will leave many people in a more desperate situation. Also, creating a vast underclass of second-class citizens with fewer rights doesn’t sound like an attractive scenario to me.

Another suggestion they put forward is targeted restriction. E.g. open immigration except for Muslims, or only for republicans, or only for men, etc. I think this concept has a lot of promise, and I laud the authors for bringing this approach up for debate. As they say in the book, it may feel very unfair, but still the overall unfairness is less than the current state. I hope that these ideas will be discussed further.

As a final remark, I will mention an idea that they do not discuss, but I wish they had: Charter cities. A problem for many is that they are not allowed to move to the US, this is true. But also, a problem for many is that they are not allowed to move anywhere at all where the government and society is not terrible! One way to attempt to address the latter problem is to create new charter cities: Places with new systems of government and legislation where people are free to move. This could give millions of oppressed people an opportunity of escape. There is a lot of land around the world, and many different types of attempts could be made, until a successful approach is found. This is also appealing for the reason that it’s better to tinker and experiment with what works, rather than committing to full-scale, radical transformation of society with unknown consequences.