This essay is part of our collection on Islam and immigration. See the full collection here. 

Five days after Muslim terrorists killed fourteen people in San Bernardino on December 2, 2015, Donald Trump called for a ban on Muslims entering the US, at least “until our country’s representatives can figure out what is going on.” A debate about the constitutionality of Trump’s suggestion immediately ensued. That debate was revived after Trump became the Republican Party’s official nominee for president at their national convention in Cleveland, and in the wake of Khizr Khan’s critical comments about Trump’s attitude toward Muslims at the Democratic National Convention last month in Philadelphia.

There is no clear-cut case to be made from the Constitution against Trump’s proposal (not to say that you couldn’t find ways to cobble one together). And were a President Trump to succeed in enacting a temporary ban on Muslims entering the US, legal challenges to the ban would probably have a hard go of it, given existing legislation and the precedent set by the numerous entry bans on various groups enacted by presidents and congresses in the past.

However, it is not the constitutionality of Trump’s proposal that I wish to discuss here. There is already a good deal of commentary on that. What I want to do instead is to analyze Trump’s proposal from the perspective of Thomistic moral theory. In other words, I want to consider it from a broader perspective, looking beyond the document that governs our particular political order. In applying Aquinas’s moral theory, I shall also be invoking his political theory, since he sees the latter as a part of the former.

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Trump’s Proposal

Before I get to my analysis, let’s get a closer look at its object. On December 7, 2015, Trump’s campaign issued a press release that begins with the following statement:

Donald J. Trump is calling for a total and complete shutdown of Muslims entering the United States until our country’s representatives can figure out what is going on.

The press release goes on to discuss polling data that supposedly reveal “great hatred towards Americans by large segments of the Muslim population.” The document cites a poll conducted by the Center for Security Policy, which claims that “‘25% of those polled agreed that violence against Americans here in the United States is justified as a part of the global jihad’ and 51% of those polled, ‘agreed that Muslims in America should have the choice of being governed according to Sharia.’” The press release then quotes Trump’s response to these claims:

Where this hatred comes from and why we will have to determine. Until we are able to determine and understand this problem and the dangerous threat it poses, our country cannot be the victims of horrendous attacks by people that believe only in Jihad, and have no sense of reason or respect for human life.

In the days that followed the press release, Trump softened the “total and complete shutdown” part of his proposal by indicating that he would make exceptions for Muslims who are US citizens, Muslims who are political officials of other countries, Muslim athletes attending sporting events, and so on.

After the terror attack on the Orlando nightclub this past June, Trump again spoke about his proposed ban:

I called for a ban after San Bernardino, and was met with great scorn. But now, many are saying that I was right to do so. And even though the pause is temporary we must find out what is going on. We have to do it. It will be lifted – this ban – when and if we as a nation can figure out how to perfectly screen these people coming into this country.

Some people have challenged the scientific quality of the Center for Security Policy poll to which the Trump campaign appealed in its original press release. Of course, Trump could concede this objection but point to the several acts of terror committed by Muslims in the US in the name of Islam in the past decade and a half (not to mention planned attacks that have been thwarted). And he need not get into a theological debate about whether these Muslims had correctly understood the teachings of their religion. For security purposes, he can say that it doesn’t really matter whether they did.

In a speech given in Youngstown, Ohio, on August 15, Trump appeared to offer a further revision of his proposal. In his remarks he floated the idea of temporarily suspending immigration only from “the most dangerous and volatile regions of the world that have a history of exporting terrorism.” This would be dramatically different from a general ban on Muslims entering the US and surely harder to take exception to.

It would seem that the Trump proposal is still quite fluid. It could continue to be trimmed or return to a more expansive form (depending on the course events take in the near future). In this essay, I shall consider the version of the proposal that emerged just after the Orlando attack, which is a kind of mean between the first and the latest versions. I would sum up that version in this way: because of the very real threat of Muslim terror, the American government should, with some important exceptions, ban Muslim travel to the US until it has worked out an effective way of screening out actual or possible terrorists. The main concern of the ban, it would appear, is the security of US citizens. Of course, some people will insist that there is a different and more sinister agenda behind Trump’s proposal, but unless credible evidence can be produced to back up these speculations, I prefer to take it at face value.

A Thomistic Analysis

Aquinas holds that the principal concern of the governing authority of any political community must be the common good of that community. While variations in historical, cultural, and social contexts will mean variations in the precise shape of this common good across political communities, certain aspects of it will be invariant.

There are certain things that are good for all human beings as human beings. These natural goods correspond to our natural inclinations. In Summa theologiae, I-II, q. 94, a. 2, Aquinas lists five of them. I formulate them in the following way: pursuing good and avoiding evil; life; creating and sustaining families and educating children; pursuing the truth about God; and creating and sustaining well-ordered communities. These goods are the basis for Thomistic natural law. (The wording I use here isn’t Aquinas’s, but I believe that it expresses what he is getting at.)

If life is among the natural human goods, then it belongs to the common good of any political community. And, evidently, life is the natural human good that is the precondition of our ability to pursue and enjoy whatever else belongs to the common good. Thus, it’s clear that the governing authority of the community has an obligation to do what it reasonably can to safeguard the lives of its citizens. So, it might look like we can settle the matter before us pretty neatly, at least if we follow a Thomistic line of thinking. Trump’s proposal corresponds to the government’s obligation to safeguard the lives of its citizens. Therefore, it seems perfectly acceptable.

This argument, despite its obvious simplicity, is to my mind a strong one. Nevertheless, I don’t think we should end the discussion here, for there are two possible—and quite legitimate—objections that should be considered. The first objection would turn the premise about the government’s duty to protect the lives of the members of a political community against the argument in which I have just employed it. Isn’t it likely that a ban on Muslim travel to the US—however temporary and however many exceptions it allows—would stir up Muslim resentment toward the US both at home and abroad and thereby put the lives of American citizens in danger? If so, wouldn’t Trump’s proposal bring about the opposite of the effect that it aims at?

This objection raises a concern that we cannot easily dismiss. However, it doesn’t provide any decisive reasons for rejecting Trump’s proposal. Rather, it shows us that the right application of the Thomistic principle in question isn’t decidable a priori but is a matter of prudential judgment. It is conceivable that reasonable people could disagree about what would be the best way to protect the lives of US citizens in this situation.

The second objection has to do with Muslim refugees or Muslims who are simply seeking a better way of life for themselves. Would it be morally permissible for the US government to turn them away because of their religion? This I believe is a more forceful objection than the previous one. A first response might go like this: on Aquinas’s understanding, the governing authority’s first obligation is to the common good of the citizens of the particular political community that it serves, not to people outside that community. Put differently, no governing authority has a duty to be altruistic, at least not if the altruism imperils the common good of the community for which it is responsible.

If there is a real security concern—and I am prepared to grant Trump that there is—then I don’t see any prima facie problem with temporarily turning away the second category of Muslims (those who are seeking a better way of life for themselves). But what about refugees? What about, for instance, people fleeing the civil war in Syria? By turning them away, even temporarily, are we not endangering their lives?

Still, there remains the as yet unsolved problem of how to screen effectively for actual or possible terrorists (although Trump’s recent suggestions on this front merit serious discussion). It’s not evident that being a refugee is incompatible with being a terrorist. (Indeed, recent German experiences point to their compatibility.) And, of course, refugees who aren’t terrorists now could later become radicalized.

I see no clear moral obligation, on Thomistic principles, to grant refugees immigrant status or to permit them to move freely within the US, especially not while there are genuine security concerns. But instead of turning them away, one solution would be to set up refugee holding camps. Whether the Muslim refugees could eventually be granted immigrant status or offered a path to citizenship could be decided at a later time. (Incidentally, section 212 of the Immigration and Nationality Act, as I read it, would permit the government even to turn away refugees when they are regarded as a security threat. What I’m proposing, then, is possibly more generous than what is envisioned by current legislation.) I realize that refugee camps can become very ugly places but that is not inevitable (consider the Kilis Oncupinar Accommodation Facility in Turkey) and, in any case, we would have to judge whether, in the specific circumstances, they would be better than the alternative.

The Question of Christian Charity

The principles that guide Aquinas’s moral theory aren’t only those of natural law. His moral theory also has a Christian dimension. In this dimension, as you might imagine, charity has a special role to play. You might expect that the obligations of charity would lead us to different conclusions than the ones to which we have already come. But I don’t think that they do.

For Aquinas, charity primarily directs us to friendship with God. But, he reasons, friends also love what belongs to the friend, such as the friend’s family, his servants, and so on. As the whole human race belongs to God, we are bound, consequently, to love all of our fellow human beings, “even our enemies,” says Aquinas.

Following Aristotle, Aquinas holds that love consists in willing the good of the person loved. Surely, this would mean, minimally, that we should help anyone we practically can in his pursuit of the natural human goods. But what if we have reasonable concerns about the threats that a particular population, or elements within it, pose to our political community’s pursuit of those same goods? Aquinas’s teaching on charity doesn’t demand that the governing authority of a political community risk the common good to assist outside groups who could endanger the common good. In Summa theologiae, II-II, q. 44, a. 7, which is a part of his treatise on charity, Aquinas explains that “no one should give way (condescendat) to his neighbor in anything evil but only in what is good.”

At this point, I think we would be brought back to the same objections and responses that we just ran through above. Taking charity into account, therefore, doesn’t lead us anywhere new.

On my analysis, there is nothing obviously morally objectionable about Trump’s proposal (according to the version of it I have been considering). He doesn’t make the provision for refugees that I suggest, but this could easily be added. Although I see no grave reasons for rejecting Trump’s proposal, I don’t claim that it can be endorsed without qualification either. In the end, the question of whether and how it should be implemented is a question of prudence that must be decided by weighing the practical pros and cons of its implementation.