The royal procession of Queen Elizabeth IWikimedia

Giving squalling infants membership in the polity: Whose idea was that, anyway?

It’s a natural question to ask, now that Donald Trump’s proposal to scrap what he calls “birthright citizenship,” or what others call Section 1 of the Fourteenth Amendment, has become a major point of contention in the 2016 election.

The Republican frontrunner’s assertion that the United States is “just about” the only country “stupid enough” to grant citizenship to all children born within its borders is easily proven false. Far from a scarlet letter of perversion, the U.S. policy is more like a badge of membership in the Western Hemisphere, where nearly all countries adhere to a version of the principle, a commonality some scholars argue is a legacy of colonial pro-immigration policies in the New World.

But the term “birthright citizenship” is also misleading. There are actually two common types of birthright citizenship in the modern world, and both are incorporated into U.S. policy. Trump and those who agree with him apparently only object to one of them.

You can be born into U.S. citizenship by being born in the United States—the principle known as jus soli, or “right of the soil.” Most countries in the Americas feature jus soli citizenship. And you can also be born into U.S. citizenship by being born to U.S. citizens, even if you’re born abroad—a concept known as jus sanguinis, or “right of blood.” “Roman law,” said University of Michigan law and classics professor Bruce Frier, “was very distinctly in the jus sanguinis category.” The policy has also frequently been incorporated into modern European states, emphasizing membership in the nation through parentage.

Yet the real irony of calling “birthright citizenship” a peculiarly American stupidity is that historically and theoretically speaking, geographical birthright citizenship is precisely as American as apple pie. That is to say: it’s English—and thoroughly monarchical in origin.

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Given his “anchor baby” rhetoric, Trump may be pleased to learn one thing: The case many scholars cite as establishing the theoretical basis for geographical birthright citizenship did indeed involve a troublemaking toddler. The toddler was a Scottish aristocrat, and the case was a property battle.

In 1603, Elizabeth I, the “Virgin Queen,” died without an heir. The solution was to give her cousin Mary’s son, James VI of Scotland, a second crown, making him James I of England. The tough part about that, according to the University of Miami law professor Kunal Parker, author of a forthcoming history of immigration and citizenship law, was that “under English law, aliens—those who were born outside the allegiance to the king—were not able to hold or convey titles of real property.” Thus, in 1608, an English court found itself answering an intriguing question: If two-year-old Scottish infant Robert Colville had been given lands in England, were his claims on those lands valid? The traditional English position at the time of the case, Parker said, “was of course because he’s Scottish and hence an alien he should not have good titles to lands in England.”

In his influential report on what has, inexplicably given the actual names of those involved, become known as Calvin’s Case, the English judge Sir Edward Coke articulated a distinctly feudal-sounding jus soli principle that formed the basis of much law to come: “Every one born within the dominions of the King of England, whether here or in his colonies or dependencies, being under the protection of—therefore, according to our common law, owes allegiance to—the King and is subject to all the duties and entitled to enjoy all the rights and liberties of an Englishman.” Furthermore, “Seeing then that faith, obedience, and ligeance are due by the law of nature, it followeth that the same cannot be changed or taken away.”

In other words: People born in the king’s lands are his subjects and owe him allegiance, while he owes them protection, and there’s nothing the subject can do about it. This idea failed to delight the Lockean consent-of-the-governed junkies of later decades and centuries. As the law professor Peter Schuck and the political-science professor Rogers Smith put it in their famous 1985 critique of U.S. immigration policy, Citizenship Without Consent, “At a conceptual level, [birthright citizenship] was fundamentally opposed to the consensual assumptions that guided the political handiwork of 1776 and 1787.”

As for the Scottish toddler? The court backed him. According to Parker, Coke’s report reasoned that “of course you owe allegiance to the physical body of the monarch, but the monarch can only give you protection in his full legal and political capacity. His full legal and political capacity in this case means as king of England and Scotland, and therefore you get protection in England and Scotland. And so therefore Calvin does not suffer the legal disabilities with respect to property that other aliens would suffer in England.”

By remaining single and childless, which left the throne open for James I, Queen Elizabeth had indirectly given the baby his English inheritance.

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Coke’s conception of subjecthood became the basis for much of what we might call nationality law throughout the British Empire. Only as that empire fell apart in the second half of the 20th century did reliance on the concepts of jus soli and subjecthood start to waver. The British Nationality Act of 1948 created a “citizen” category, and in the 1970s and 1980s requirements for special ties to the United Kingdom were introduced to jus soli citizenship, eventually requiring the permanent residency in the U.K. of at least one parent. The language of subjecthood was phased out.

Strangely, the principle of jus soli wound up flourishing in one of the first territories to throw off British imperial rule—the United States—and in the service of an entirely different set of norms.

After the 13 colonies gave Coke and King George the slip in the American Revolution, the new country, divided by slavery, largely left questions of citizenship to the states. State common law was supplemented by only a few federal statutes on naturalization and citizens’ children. In 1857, the U.S. Supreme Court’s notorious Dred Scott decision denied blacks jus soli citizenship. “For black inhabitants, at least,” wrote the Emory law professor Polly Price in a 1997 article, “Dred Scott invoked a rule more akin to the jus sanguinis, while the rule of territorial birthright citizenship appears to have been a settled rule for white inhabitants.” When Radical Republicans forced through the Fourteenth Amendment after the Civil War, they intended it as an explicit reversal of Dred Scott. The new, universal jus soli principle was supposed to guarantee the citizenship of freed slaves.

“What’s paradoxical in this whole birthright-citizenship story,” said Parker, “is of course that this feudal rule—the idea of perpetual allegiance based on birth within the monarch’s realm—ends up securing the membership of blacks, and of course also of immigrants.”

Schuck and Smith, scholars who are frequently cited by opponents of birthright citizenship in the United States, found the intellectual genealogy of birthright citizenship troubling. “In a polity whose chief organizing principle was and is the liberal, individualistic idea of consent,” they reasoned, “mere birth within a nation’s border seems to be an anomalous, inadequate measure of expression of an individual’s consent to its rule and a decidedly crude indicator of the nation’s consent to the individual’s admission to political membership.”

On the other hand, consider the apple pie. It would take a seriously eccentric sort of American patriot—not to mention a seriously eccentric palate—to get excited about that 1390 recipecompiled … by the master-cooks of King Richard II.” But that recipe from Connecticut in 1796 is a different story. Turns out, once you ditch the figs and saffron, apple pie isn’t half bad.

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