While the classic anti-migrant playbook focuses on falsely accusing migrants of spreading disease, doing crimes, stealing jobs, and using resources, there is also the more recent addition of accusing migrants of being terrorists, especially Muslim migrants.  This is then used to “justify” anti-migrant actions.

On the one hand, it is tempting to dismiss this as political posturing and pandering to fear, racism and religious intolerance. On the other hand, it is worth considering legitimate worries under the posturing and the pandering. One worry is that terrorists could masquerade as refugees. Another worry is that refugees might be radicalized and become terrorists.

In politics, it is unusual for people to operate based on consistently held principles. Instead, views usually reflect how a person feels or what they think about the political value of a position. However, a proper moral assessment requires considering migration in terms of general principles and consistency.

In the case of the refugees, the general principle justifying excluding them would be something like this: it is morally acceptable to exclude groups who might include people who might pose a threat. This principle seems, in general, reasonable. After all, excluding people who might present a threat serves to protect people from harm.

Of course, this principle is incredibly broad and would justify excluding almost anyone and everyone. After all, nearly every group of people (tourists, refugees, out-of-staters, men, Christians, atheists, cat fanciers, football players, and so on) include people who might pose a threat.  While excluding everyone would increase safety, that would be absurd. As such, this general principle should be refined. For example, considering the odds that a dangerous person will be in the group, the harm such a person is likely to do, and the likely harms from excluding that group.

According to Cato institute, “A total of 237 foreign-born terrorists were responsible for 3,046 murders on US soil from 1975 through the end of 2024. The chance of a person perishing in a terrorist attack committed by a foreigner on US soil over those 50 years was about 1 in 4.6 million per year. The hazards posed by foreigners who enter in different ways vary considerably. For instance, the annual chance of being murdered in an attack committed by an illegal immigrant terrorist is zero.” Thus, arguing against immigration based on an alleged threat of terrorism is absurd. This is not to say that we should not be vigilant, just that if the goal is to protect Americans, then the resources could be better used in other ways. Such as funding health care.

It might be countered, using hyperbolic rhetoric, that if even one terrorist gets into the United States, that would be too many. While one bad thing is one too many, would it be reasonable to operate on a principle that the possibility of even one bad outcome warrants strict regulation? That would generally seem to be unreasonable. This principle would justify banning guns, peanuts, swimming pools and cars. It would also justify banning tourists and visitors from other states. After all, tourists and people from other states do bad things in states from time to time. It would also seem to justify banning birth. After all, we can be sure at least one person born in the future will be a murderer. As such, the idea of basing policy on the notion that one is too many is absurd.

There is, of course, concerns about political risk. A politician who supports allowing Muslim migrants to come to America will be savaged by the right if even a single incident happens. This, of course, would be no more reasonable than vilifying a politician who supports the Second Amendment just because a person is shot to death in their state.  But reason is usually absent in the realm of political punditry.

Another factor to consider is the harm that would be done by excluding such migrants, especially refugees. If they cannot be settled someplace, they will be condemned to live as involuntary nomads and suffer all that entails. There is also the ironic possibility that excluded refugees will become, as pundits like to say, radicalized. After all, people who are deprived of hope and are treated as pariahs tend to become a resentful and some might become terrorists. There is also the fact that banning Muslim refugees and migrants provides propaganda for terrorist groups.

Given that the risk is very small and the harm to the refugees and migrants would be significant, the moral thing to do is to allow migrants and refugees into the United States. Yes, one of them could be a terrorist. But so could a tourist. Or some American coming from another state. Or already in the state. While some right-winger might accuse me of thus supporting open borders, nothing I say entails that. Refugees and migrants need to be properly vetted, especially after our attack on Iran. While I am not an expert on terrorism, I would expect Iran to step up its efforts against the United States.

In addition to utilitarian calculation, an argument can also be based on moral duties to others, even when acting on such a duty involves risk. In terms of religious-based ethics, a standard principle is to love thy neighbor as thyself, which requires helping refugees and migrants even at a slight risk. There is also the golden rule.

As a closing point, we Americans love to make claims about the moral superiority and exceptionalism of our country. Talk is cheap, so if we want to prove our alleged superiority and exceptionalism, we must act in an exceptional way. Excluding people and refusing to help them because we are afraid shows a lack of charity, compassion and courage. This is not what an exceptional nation would do.