The attempt to end birthright citizenship in the United States is an attempt to reverse history, to push our nation back, way back, before the Dred Scott decision of 1857 and the secession crisis that soon delivered the nation into the Civil War. Calling this action “unconstitutional” is utterly inadequate; the maneuver is the soiling of sacred text with profane lies.

Birthright citizenship is a shield of protection to anyone born in this country, as close to a national self-definition as we have; it is our legal DNA. Section 1 of the Fourteenth Amendment should be emblazoned on small laminated cards and carried in every American’s pocket. The language is amply clear:

All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the state wherein they reside.

That language is as fundamental to the Constitution as any other provision, perhaps even more important to the survival and growth of our pluralistic republic than the First Amendment, which protects free speech, free press, the right of assembly, and the right to petition the government. It is as inherent to constitutional function as federalism itself.

[Read: The Attack on Birthright Citizenship Is a Big Test for the Constitution]

The Trump administration now scoffs at this history, purporting to end this guarantee with an executive order signed on Donald Trump’s first day back in the Oval Office and tragically titled, in a fantastic act of Orwellian doublespeak, “Protecting the Meaning and Value of American Citizenship.” The administration makes a phony originalist argument based on the claim that the Fourteenth Amendment’s guarantee extended only to the freedmen and their descendants. Quite the contrary, the amendment’s authors explicitly envisioned the immigrant population and its descendants as part of their plan. Congressman John Bingham, Section 1’s author, defended the amendment by drawing on the authority of the Constitution’s Framers, who had “invited the workers and builders whose honest toil clothes and shelters nations,” and who hailed from “every civilized nationality” to become “citizens of the Republic.” This is why, in blocking Trump’s order last week, the Federal District Court Judge John C. Coughenour said without caveat: “This is a blatantly unconstitutional order.”

Section 1’s origins lie deep in our past. It is rooted in the petitions of African Americans during and after the American Revolution that demanded freedom and natural rights for their service to the patriot cause. It stems from many ideas and strategies of the British and American abolition movements. It echoes Thomas Jefferson’s inclusion of equality among “these truths” in the Declaration of Independence and Abraham Lincoln’s use of the same word in the Gettysburg Address, as well as his full-throated embrace of immigration well before the Civil War. Its most direct and powerful harbinger is the emancipation of nearly 4 million slaves in the midst of the war. Without that greatest transformation in American history, there would be no Fourteenth Amendment—no birthright citizenship and no equal-protection clause either, a codification just as sacred.  

Most profound, birthright citizenship is rooted in the blood of more than 700,000 Americans who died in the Civil War, a catastrophe that made possible what most historians now call the “second founding” of America. The rebirth harkened in the Fourteenth Amendment is the core of this phrase’s meaning. The Trump administration’s desire to obliterate birthright citizenship is part of a larger quest to undo most of this egalitarian tradition, to shift American history into a kind of permanent reverse gear back to an age of secure constitutional white supremacy.

[Read: The Coming Assault on Birthright Citizenship]

One cannot overstate the gravity of Trump’s proposed action, nor the historical ignorance on which it stands. The original Republicans who crafted birthright citizenship into the amendment were doing nothing less than harvesting the greatest results of the Civil War, making good on the promise of freedom for millions of any creed, color, or national origin at the time and for all time to come. Section 1 explained to the world what that war had meant. To erase any part of it now is to tarnish the legacy of William McKinley, Trump’s new favorite president, who fought in the Battle of Antietam. The Union victory there is what prompted the Emancipation Proclamation.

For Bingham, a deeply Christian abolitionist Republican from Ohio, this debate went back at least to the 1850s crises over the expansion of slavery. In 1858 he said, “Every man knows that under our free institutions, every person born of free parents within the jurisdiction of the United States … is a citizen of the United States.” Bingham, of course, overestimated such consensus, because Chief Justice Roger B. Taney in Dred Scott v. Sandford had ruled for a 7–2 majority of the Supreme Court the previous year that Black people possessed “no rights” whatsoever under American law. One of the grand purposes of the Fourteenth Amendment was to relegate the Dred Scott decision to history.

By the winter of 1866, as Congress debated the content of an amendment, it faced many overwhelming obstacles, especially bone-level, historical racism and the doctrine of federalism that fundamentally protected states’ rights. Congress had just fought an all-out war to restore the Confederate states to the Union and to end slavery with an overwhelming use of federal power.

But the Republicans, despite fierce debates, were confident. “I can hardly believe,” wrote Thaddeus Stevens, the radical floor manager for his party, “that any person can be found who will not admit that every one of these proposals is just.” They knew exactly what they intended to achieve. Bingham defended the amendment as protection of the “in-born rights of every person.” Stevens thought they had to “fix the foundations of the government on principles of eternal justice.” Senator Lyman Trumbull saw them advancing principles “which the great Author of all has implanted in every human breast.” They believed that they were enacting justice and morality, not only for freed slaves but for the country’s immigrant future, a fact they deeply understood because they had lived through the recent waves of Irish and German immigration.

[Read: The Real Origins of Birthright Citizenship]

As for states’ rights, Bingham had a constant answer. For “generations to come,” he announced, he sought to “arm Congress … with the power to enforce the Bill of Rights as it stands in the Constitution … in the states.” In the states, by federal power.

In floor debates, Bingham spoke with great eloquence about the purposes of the amendment. “The day of the freedman’s deliverance has come,” he declared, “not without suffering, not without sorrow, not without martyrdom, not without broken altars and broken hearts.” But now he saw potential days of glory, not only for ex-slaves but for the immigrant. The Constitution could now “provide that no man, no matter what his color, no matter beneath what sky he may have been born, no matter in what disastrous conflict or by what tyrannical hand his liberty may have been cloven down, no matter how poor, no matter how friendless … shall be deprived of life or liberty or property without due process of law.” Above everything, “all persons born” here were forever citizens.  

Trump and his allies have picked a fight over this crucial provision in the Constitution. Americans have to engage the fight, in the courts and with every mode of persuasion. Trump and his allies’ vision is an egregious abuse of real history and the new Constitution it forged in the 1860s. If they succeed, then Grant has surrendered to Lee at Appomattox.

The purpose of the Fourteenth Amendment was to settle once and for all the question of racial citizenship, forever preventing the subjugation of one class of people by another. Donald Trump’s executive order purporting to end birthright citizenship is an attempt to reverse one outcome of the Civil War, by creating a permanent underclass of stateless people who have no rights they can invoke in their defense.

In 1856, in the infamous Dred Scott decision that declared that Black people could not be American citizens, Chief Justice Roger Taney wrote that as “a subordinate and inferior class of beings,” Black people had “no rights which the white man was bound to respect.” Yes, the Declaration of Independence had stated that “all men are created equal,” but “the enslaved African race were not intended to be included.”

Frederick Douglass, who argued that the Constitution did not sanction slavery, responded to the Taney decision by saying that one could find a defense of slavery in the Constitution only “by discrediting and casting away as worthless the most beneficent rules of legal interpretation; by disregarding the plain and common sense reading of the instrument itself; by showing that the Constitution does not mean what it says, and says what it does not mean, by assuming that the written Constitution is to be interpreted in the light of a secret and unwritten understanding of its framers, which understanding is declared to be in favor of slavery.” Sounds familiar.

[David A. Graham: It’s already different]

Trump’s executive order similarly rewrites the Constitution by fiat, something the president simply does not have the authority to do. The order, which purports to exclude the U.S.-born children of unauthorized immigrants from citizenship, states that such children are not “subject to the jurisdiction” of the U.S. and therefore not included in the amendment’s language extending citizenship to “all persons born or naturalized in the United States.” This makes no sense on its own terms—as the legal scholar Amanda Frost wrote earlier this month, “Undocumented immigrants must follow all federal and state laws. When they violate criminal laws, they are jailed. If they park illegally, they are ticketed.” The ultraconservative Federal Judge James C. Ho observed in 2006 that “Text, history, judicial precedent, and Executive Branch interpretation confirm that the Citizenship Clause reaches most U.S.-born children of aliens, including illegal aliens.”

As such, Trump’s executive order on birthright citizenship is an early test of the federal judiciary, and of the extent to which Republican-appointed judges and justices are willing to amend the Constitution from the bench just to give Trump what he wants. They have done so at least twice before, the first time by writing the Fourteenth Amendment’s ban on insurrectionists running for office out of the Constitution, and the second time by seeking to protect Trump from prosecution by inventing an imperial presidential immunity out of whole cloth. But accepting Trump’s attempt to abolish birthright citizenship would have more direct consequences for millions of people, by nullifying the principle that almost anyone born here is American.

In the aftermath of the Civil War, white southerners tried to restore, at gunpoint, the slave society that had existed prior to the war, notwithstanding the Thirteenth Amendment’s abolition of slavery. Republicans in Congress passed the Fourteenth Amendment to secure equal citizenship and the Fifteenth Amendment to protect the right to vote regardless of race, amendments that guaranteed political and civil equality. The Civil War amendments, the work of the Republican Party, are the cornerstone of multiracial democracy in the United States. Despite this historic accomplishment, for the past 80 years or so, the party of Lincoln has aimed its efforts at repealing or nullifying them.

“Adopted as part of the effort to purge the United States of the legacy of slavery, birthright citizenship, with which the Fourteenth Amendment begins, remains an eloquent statement about the nature of American society, a powerful force for assimilation of the children of immigrants, and a repudiation of a long history of racism,” the historian Eric Foner writes in The Second Founding, a history of the Civil War amendments, though he is cautious to note that these principles were not always respected by the government—Jim Crow and Japanese internment being obvious examples. Birthright citizenship was “a dramatic repudiation of the powerful tradition of equating citizenship with whiteness, a doctrine built into the naturalization process from the outset and constitutionalized by the Supreme Court in Dred Scott.”

This detachment of American citizenship from whiteness was one of the parts of the Fourteenth Amendment that Democrats, at the time the party of white supremacy, hated the most. “Democratic members of Congress repeatedly identified American nationality with ‘the Caucasian race,’ insisted that the government ‘was made for white men,’ and objected to extending the ‘advantages’ of American citizenship to ‘the Negroes, the coolies, and the Indians,’” Foner writes.

Trump’s immigration braintrust sees things similarly. In emails with conservative reporters, Trump’s point man on immigration, Stephen Miller, praised articles attacking the 1965 repeal of racist restrictions on immigration that had been passed in 1921 and were intended to keep out nonwhite people, Southern and Eastern Europeans, and Jews. These laws again redefined American citizenship in racist terms, and helped inspire the Nazis. The end of those restrictions meant that more nonwhite immigrants were able to gain citizenship in the United States, a phenomenon conservatives have dubbed a “Great Replacement,” borrowing a concept from white-supremacist sources. That the Trump coalition now includes people who would have been shut out by Miller’s preferred immigration policies does not change the fact that Trump’s immigration advisers view the decline of the white share of the population as an apocalyptic occurrence that must be reversed. It is no accident that this project begins with the nullification of constitutional language guaranteeing citizenship regardless of race or country of origin.

[Martha S. Jones: The real origins of birthright citizenship]

Republicans have made significant inroads among nonwhite voters in the past few years. Their reasons for supporting Trump change neither the intent of his entourage nor the effects of his policies. A successful repeal of birthright citizenship would mean the so-called pro-life party creates a class of stateless infants, a shadow caste mostly unprotected by law. It would require Americans to prove their citizenship time and time again, and leave them vulnerable to administrative errors that could endanger proof of their status. These burdens would likely fall disproportionately on those nonwhite people Trumpists see as their “replacers,” no matter how enthusiastic about Trump they might be.

Since the rise of Trump, the once-fringe idea that the Fourteenth Amendment does not confer citizenship on the children of undocumented immigrants has gained traction among ambitious conservatives whose malleable principles allow them to shape themselves to Trump’s whims. By November of 2024 the aforementioned Ho, who had previously written a detailed law-review article rejecting such theories, had become a bombastic, partisan Trumpist judge; he carefully retraced his steps and insisted that the birthright-citizenship clause doesn’t apply in the case of immigrant “invasion,” substituting Fox News talking points for legal reasoning.

This is the level of respect for the Constitution one can expect from conservative jurists in the Trump era. Whatever Trump says is correct. What the original framers of the Fourteenth Amendment understood was that the necessities of multiracial democracy demand more than bowing and scraping before this sort of lawlessness. For now, neither party’s political leadership seems up to the task.

A politically powerful opponent of birthright citizenship railed that the United States cannot “give up the right” to “expel” dangerous “trespassers” who “invade [our] borders,” “wander in gangs,” and “infest society.”

Was this Donald Trump speaking in 2024? No, the quote is from an 1866 speech on the Senate floor by Senator Edgar Cowan of Pennsylvania, a leading opponent of adding a provision to the U.S. Constitution granting citizenship based solely on birth on U.S. soil. Who were the “invaders” that Senator Cowan so feared? “I mean the Gypsies,” Cowan explained, despite offering no evidence that Roma migration posed a risk to the United States.

Senator Cowan lost the fight. In 1868, the nation ratified the Fourteenth Amendment, the first sentence of which guarantees birthright citizenship. The amendment invalidated the Supreme Court’s infamous 1857 decision in Dred Scott v. Sandford, which declared that no Black person could ever be a U.S. citizen. Equally important, the Constitution now guaranteed citizenship to the children of immigrants born on U.S. soil, “no matter from what quarter of the globe he or his ancestors may have come,” as one senator later put it in a speech to his constituents.

[Martha S. Jones: Birthright citizenship was won by freed slaves]

More than 150 years later, Trump has vowed to end birthright citizenship on “day one” of his new administration for children without at least one parent who is a citizen or green-card holder. He made that announcement in a three-minute video prominently posted on his campaign website, which he repeated in an interview with NBC’s Meet the Press last month.

In 2025, the end of birthright citizenship is more than just an applause line at the Conservative Political Action Conference. It has a genuine, if slim, chance of making its way into law. If it does, it will upend the lives of millions, and create a caste system in which a new set of people—native-born non-Americans—can never work or live in the open.

This prospect ought to be taken seriously. How would President Trump implement such a plan? Is it constitutional? And would the U.S. Supreme Court back him up?

The first question is easy, because Trump has told us exactly how he intends to proceed. In the video, the president-elect commits to issuing an executive order on January 20, 2025, that would deny citizenship not only to the children of undocumented immigrants but also to those born to parents who both are legally in the United States on a temporary visa for study or work. (Trump’s order as proposed would apply only to children born after it is issued.)

The consequences would be immediate. Trump says he will order government officials to deny these children passports and Social Security numbers. They will be prohibited from enrolling in federal programs such as Medicaid, the Children’s Health Insurance Program, and the Supplemental Nutrition Assistance Program, and likely state benefits as well.

As adults, if all goes according to Trump’s plan, they will be barred from voting, holding elected office, and serving on juries. States could deny them a driver’s license and block them from attending state universities. They would be prohibited from working in the United States, and any U.S. citizen who employs them could be fined or even jailed under federal immigration laws. Many would be rendered stateless. Perhaps worst of all, they would live in perpetual fear of being deported from the only country in which they have ever lived.

[Read: Trump’s murky plan to end birthright citizenship]

Ending birthright citizenship for these children would affect everyone in America. Everyone would now have to provide proof of their parents’ citizenship or immigration status on the date of their birth to qualify for the rights and benefits of citizenship. The new law would necessitate an expanded government bureaucracy to scrutinize hospital records, birth certificates, naturalization oaths, and green-card applications.

Lawsuits are sure to follow, which leads to the second question: Will Trump have the constitutional authority to end birthright citizenship for the children of undocumented immigrants?

Per the text of the Constitution, the answer is a hard no. Some constitutional provisions are fuzzy, but the citizenship clause is not one of them. It states: “All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside.”

Even the deeply racist Supreme Court back in 1898 couldn’t find any wiggle room in that language. Just two years before, in 1896, the Court had somehow read the Constitution’s equal-protection clause to permit “separate but equal” in Plessy v. Ferguson, ushering in the Jim Crow era. But when the U.S. government argued in United States v. Wong Kim Ark that the children of Chinese immigrants were not birthright citizens, the justices balked. The language granting citizenship to “all persons born” in the United States was “universal,” the Court explained, restricted “only by place and jurisdiction.” More recently, the Supreme Court reaffirmed that point, stating as an aside in a 1982 opinion addressing the rights of undocumented children to attend school: “No plausible distinction with respect to Fourteenth Amendment ‘jurisdiction’ can be drawn between resident aliens whose entry into the United States was lawful, and resident aliens whose entry was unlawful.”

Despite the clear text and long-standing judicial precedent, Trump claims that undocumented immigrants and their children are not “subject to the jurisdiction” of the United States, and so fall within the exception to universal birthright citizenship.

That is nonsense. Undocumented immigrants must follow all federal and state laws. When they violate criminal laws, they are jailed. If they park illegally, they are ticketed. They are required to pay their taxes and renew their driver’s license, just like everyone else. Trump certainly agrees that undocumented parents of native-born children can be deported for violating immigration laws at any time. So in what way are these immigrants and their children not subject to U.S. jurisdiction?

The citizenship clause’s exception for those not “subject to the jurisdiction” of the United States applies only to children born to members of American Indian tribes and the children of diplomats, as Congress explained when drafting that language in 1866. In contrast with undocumented immigrants, both groups owe allegiance to a separate sovereign, and both are immune from certain state and federal laws. (Native Americans were granted birthright citizenship by federal statute in 1924.)

As nonsensical as they are in an American context, Trump’s ideas didn’t come out of nowhere. In 1985, the law professor Peter Schuck and the political scientist Rogers Smith wrote an influential book, Citizenship Without Consent, arguing that the Fourteenth Amendment’s citizenship clause did not apply to the children of undocumented immigrants. These scholars asserted that “immigration to the United States was entirely unregulated” before the 1870s, and so there was no such thing as an “illegal immigrant” and likewise no intent to grant birthright citizenship to their children. Many scholars and commentators, including some members of Congress, have repeated that same claim. In 2015, the law professor Lino Graglia testified before the House Judiciary Committee that “there were no illegal aliens in 1868 because there were no restrictions on immigration.” Then-Representative Raúl Labrador repeated the same point at that hearing, asserting as fact that there was “no illegal immigration when the Fourteenth Amendment came into being.” In an op-ed in June 2023, a former Department of Homeland Security policy adviser declared, “There were no immigrant parents living unlawfully in the United States” in the 19th century.

These critics have their facts wrong. In a recent law-review article, the legal scholars Gabriel Chin and Paul Finkelman explained that for decades, Africans were illegally brought to the United States as slaves even after Congress outlawed the international slave trade in 1808, making them the “illegal aliens” of their day. The nation was well aware of that problem. Government efforts to shut down the slave trade and deport illegally imported enslaved people were widely reported throughout the years leading up to the Civil War. Yet no one credible, then or now, would argue that the children of those slaves were to be excluded from the citizenship clause—a constitutional provision intended to overrule Dred Scott v. Sandford by giving U.S. citizenship to the 4.5 million Black people then living in the United States.

[Read: Birthright citizenship wasn’t born in America]

Even so, these ideas have gained traction in the right-wing legal community—a group that will be empowered in Trump’s next term. The Fifth Circuit judge James C. Ho, who is regularly floated as a potential nominee to the Supreme Court, recently said in an interview that children of “invading aliens” are not citizens, because “birthright citizenship obviously doesn’t apply in case of war or invasion”—a reversal of his previous position on this issue. (This is the judicial equivalent of shouting, “Pick me! Pick me!”) Never mind that undocumented immigrants—a majority of whom entered the United States legally and then overstayed their visa—don’t qualify as invaders under any definition of the word. And never mind that there is no support for that idea in either the Constitution’s text or its history. In 1866, Senator Cowan opposed granting citizenship to the children of the “flood” of Chinese immigrants into California, as well as to Gypsy “invaders” of his own state. His colleagues pointed out that the only invasion of Pennsylvania was by Confederate soldiers a few years before. Birthright citizenship, they explained, would ensure that the United States would never revert back to the slave society that the Confederates invaded Pennsylvania to preserve.

In truth, all of these baseless arguments are window dressing for the real goal. The Fourteenth Amendment’s overarching purpose was to end a caste system in which some people had more rights under the law than others. To be sure, that ideal has always been a work in progress. But many opponents of birthright citizenship don’t even hold out that ideal as a goal; they would rather bring caste back, and enshrine it in our laws.

If birthright citizenship were to end tomorrow for children without at least one parent who was a citizen or lawful permanent resident, it would bar from citizenship hundreds of thousands of people each year. These people wouldn’t be eligible to participate in our democracy, and they would be forced to live and work in the shadows, as would their children and their children’s children. The end of birthright citizenship would create a caste of millions of un-Americans, locked in perpetuity into an inferior, exploitable status. Ironically, if Trump were to succeed in ending birthright citizenship, he would preside over the most dramatic increase of undocumented immigrants in U.S. history.

That brings us to the third question: Would five members of the Supreme Court uphold Trump’s proposed executive order?

No sitting justice has addressed this question directly. At his confirmation hearing in 2006, Justice Samuel Alito was asked whether he thought the children of undocumented immigrants qualified for birthright citizenship under the Fourteenth Amendment. He refused to answer on the grounds that a future case might come before him, but he also observed: “It may turn out to be a very simple question. It may turn out to be a complicated question. Without studying the question, I don’t know.” Justice Amy Coney Barrett declined to respond to the same question for the same reason. (These two justices also dodged questions about whether they would overturn Roe v. Wade on those grounds.)  

The Georgetown law professor Steve Vladeck, an expert on the Supreme Court, believes that, at most, “two” or “maybe … even three justices” on the current Court would vote to end birthright citizenship. But all it takes is five, and the Court’s composition may well change. Trump appointed three justices during his first term in office, and he could appoint a few more before the end of his second. It is they who will have the last word.