In the United States, discussions of immigration start from the assumption that a nation has a sovereign right to refuse admittance to anyone, and that admittance is at its discretion. Such a stance fails to recognize that all migrants, regardless of legal status, are rights-bearing humans. The only legal concession that the United States makes to this reality is that those who are present in the United States are entitled to Due Process and First Amendment rights. Even this has not been explicitly confirmed by Supreme Court decision, though it is a widely held opinion, professed publicly even by the late Justice Antonin Scalia. Lately, even this modicum of decency has been discarded by the current regime, which actively seeks to deny due process and persecute speech, even in defiance of court orders.
In fact, due process does not adequately encompass the international rights that all humans bear. The first exponent of what we now call international rights was Francisco de Vitoria (c 1483-1546). This Spanish theologian notably opposed absolute sovereignty, holding that even sovereigns must respect the law of nations and human right. A sovereign cannot wage war whenever he pleases, but must have a cause that is just, not merely in his own eyes, but in the consideration of many wise men, and that is defensive. A mere difference in religion is not a just cause, nor is the desire for territory or the glory of a prince. A sovereign is also obligated to treat his subjects well. If he denies them their basic right and becomes a tyrant, other nations may and should wage a just war on behalf of his subjects against him.
Vitoria started from the position that humans have a natural right of society and communication, from which he derived a social solidarity of humankind. This solidarity does not permit that any one group should have absolute rights over others. Nor does the division of the world into particular polities and private holdings abrogate this natural right of society. Thus even sovereigns are bound to permit people of all nations to navigate the seas and rivers, to grant the use of ports necessary to such navigation, and to permit people to trade with those of any nation. People also have the right to travel or migrate anywhere in the world. This natural right, which antecedes the existence of nations and indeed gave birth to them, cannot be limited unless some positive harm results from it. Note that the default assumption is that the sovereign must permit migration. Some reason must be given for limiting it. The right of the people to migrate is primary.
This change in perspective also requires a change in attitude toward the dignity of those of other nations. They are not some second-degree humans pleading for admission. They are fully equal in dignity, and have a right that must be respected. Thus Vitoria famously considered that the chieftains of the Indies had sovereign rights equal to those of European princes, and were true lords of their territories before the arrival of the Spanish. They remained rights-bearing subjects even after the conquest, and were owed good treatment and respect for their persons and property. These were, needless to say, controversial positions at the time, but incredibly they prevailed to the extent that slavery was abolished in New Spain. Vitoria reminded the Spaniards that they were the migrants to another country, and just as they had been admitted, so too must they respect the rights of others.
An analogous situation appears in the southwestern United States, a territory where southerners first entered Mexico as migrants, and eventually took over by conquest. Now they should respect the rights of those who remained in the new territories, as well as any new inhabitants who should migrate. Vitoria says that the sovereign is obligated not merely to admit foreigners, but to receive them well, as a precept of natural law. They must be treated humanely, and should not exile guests who have committed no crime.
The universality of the ancient right of hospitality in the civilized ecumene is well attested, and likely familiar to many through Biblical stories. The sacredness of this right, which includes providing food and shelter to the wayfarer, is based on a sense of human solidarity and the need to travel freely across the land to seek subsistence. Humans have always migrated when their homelands are scarce in resources; indeed our very physiology is designed for long-distance travel. It is a monstrous fiction, only lately developed by some countries in the nineteenth-century, that migration without legal approval is itself a crime meriting exile.
Making this adjustment in thinking would require a humiliation of American exceptionalism, the idea that the U.S. should bow to no principle outside its own traditions. Early on, the American judiciary decided that there was no common law binding at the federal level, and that international law could provide no guidance for internal affairs, though the law of nations was indeed respected in matters of commerce and navigation, as well as the law of comity. This generally inward-looking attitude, recognizing no wisdom to be received from without, may seem ironic since our so-called “American” traditions are mostly derived from European culture. Yet we ourselves are in a self-imposed exile from Europe, deliberately cutting ourselves off in many ways in order to set out on our own course. In the last half century, an increasingly integrated world no longer permits this isolation, and those who try to revert to it must resort to ever more brutal measures, even against fellow citizens. The biggest irony is that most of these isolationists profess to be Christians, yet humility is furthest from their hearts and they have forgotten the Biblical precept of treating “strangers” (i.e., foreigners) with compassion and as fellow natives since we were once strangers. (Lev. 19:33-34)
If it was wrong for monarchs to claim absolute sovereignty, subject to no higher moral principle, it is no less wrong for a republic to do so. The American error of claiming absolute sovereignty makes us vulnerable to a moral blindness that can prevent us from seeing tyranny, and even make us welcome it. Such a claim may have seemed alarmist until very recently, but so many of the dictators of the twentieth century claimed to be acting for the good of the people or the nation that we should have alarms sound whenever someone repeats this nativist nonsense.