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It turns out that walls can’t always be seen. Donald Trump may never build his “great, great wall,” but that doesn’t mean he isn’t working to wall Americans in. It’s a story that needs to be told.

This past month, for instance, claims of ISIS’s near-total defeat in Syria have continued to mount. As a result, numerous foreigners who had traveled there to fight for, or support, the caliphate have appealed to their home countries to take them back, presumably to stand trial for their support of terrorism. Germany, Great Britain, New Zealand, and other nations have crafted responses that vary from lukewarm acceptance to outright denial of their citizenship status.

On that score, Donald Trump’s White House hasn’t just led the way, but has used the occasion to put yet more concrete and steel into the great wall his administration has been constructing around the very idea of what it is to be an American. Here in the United States, where the Statue of Liberty has been a welcoming beacon for more than a century, the Trump administration’s response has not just been a fierce aversion to the return of such people, but the use of one of them to help redefine ever more narrowly the very idea of citizenship, of who belongs to this country. In the rejection of the citizenship of a former ISIS bride with child, the president and his advisers have, in an unprecedented way, refused to uphold the rights of US-born citizens, let alone naturalized ones.

Get Out and/or Stay Out

Donald Trump arrived in the Oval Office with an expressed desire to take an axe to the lawful notion of citizenship as either a right or a promise. In the first days of his presidency, he promptly began reducing the number of individuals who might someday be eligible for US citizenship with a Muslim ban against the arrival of anyone from seven largely Muslim countries. During those first days in power, the president also issued an executive order aimed at specifically reducing the number of refugees from Syria who could enter the country, even as he actively advocated for the building of his great wall on our southern border to keep out Mexicans and Central Americans.

But walling Americans in and keeping others out proved only to be a starting point for the most xenophobic president the country had elected in at least a century. On becoming president, Trump made it crystal clear that he meant to reduce the number of noncitizens already living here as well. Yet another of his early executive orders was aimed at rounding up and deporting illegal immigrants who had been in this country, often for decades.

His promise and initial plan, never implemented, was to eliminate the prospect of future citizenship not just for undocumented immigrants already here, but for their children born here who, under the law, were certainly US citizens. And he was true to his word. Over 2017 and 2018, he deported nearly half a million individuals who had come here illegally, many of whom had, until then, lived productive lives in this country for years, if not decades. So, too, he continued to threaten DACA, or the “dreamers” program, designed to provide undocumented immigrants who arrived as children with protection against deportation. When it comes to that program, his intent is obvious, even if the courts and Congress have slowed him down so far.

Meanwhile, he also turned to naturalized citizens. On them, the 14th Amendment is clear. It grants citizenship to all persons “born or naturalized in the United States and subject to the jurisdiction thereof.” Under US law, denaturalization can occur only in certain situations, such as if an individual lies on his or her application for citizenship or is guilty of bad conduct—such as membership in a terrorist organization or an other-than-honorable discharge from the armed forces—in the first five years of citizenship.

During Trump’s presidency, there has been an all-out effort to find and prosecute such cases. Between 1990 and 2017, according to the National Immigration Forum, the Department of Justice filed an average of 11 cases of this sort a year. In 2017, that number more than doubled, and 2,500 new investigations were reportedly opened. In June 2018, the DHS even announced plans to create a new office in Southern California, whose focus would be uncovering cases ripe for denaturalization.

From undocumented immigrants and asylum seekers to refugees, DACA kids, and naturalized citizens, the pattern has been evident and the message the same: “Get out and/or stay out.” Despite a powerful xenophobic period early in the 20th century, this attitude has hardly been the essence of a country that, for most of its history, has welcomed strangers and given hope to those in search of safety, security, and the rights and liberties of America’s promise.

No longer. In September 2017, using an American foreign fighter designated as John Doe, the administration went after the concept of dual citizenship, too. Doe had been captured by Kurdish militia in Syria and was then handed over to US forces in Iraq. A dual US-Saudi citizen, he was not brought to this country to be investigated and possibly tried, but secretly held in military detention in Iraq, while being denied access to a lawyer. When the news of his detention was leaked to the media, lawyers at the ACLU filed a habeas corpus petition challenging it. The courts then put limitations on the government’s plan to transfer this citizen to a third country. Finally, he was reportedly released to Bahrain to join his wife and daughter.

The Ultimate Slippery Slope

Recently, a providential ISIS case has allowed the Trump administration to turn more directly to the denial of citizenship for those born in this country.

Two weeks ago, lawyers representing a young US-born woman, Hoda Muthana, filed papers in the District of Columbia on behalf of her father, challenging the administration on her fate. She had traveled to Syria in 2014, had become an ISIS bride, had borne a child, and now is asking to return to the United States with her son. The Trump administration has barred her from doing so, denying that she is even a citizen, despite the fact that she was issued US passports in 2005 and again in 2014 and is the citizen of no other country. The government’s decision is based on the false claim that, though she was born in New Jersey, her father was then still a Yemeni diplomat serving in the US on a diplomatic visa. Muthana, her family, and her lawyers dispute this claim, correctly insisting that she was born after his visa had ended. At that time, her mother, they also point out, was a legal permanent resident.

At the age of 20, Hoda Muthana, brought up in Alabama, was reportedly radicalized by ISIS online. She then took the money her parents had provided for tuition at the University of Alabama and absconded to Syria. Her goal: to become an ISIS bride. She married an ISIS fighter and bore him a son. When her husband was killed, she married another fighter, and yet another after his death. Online, she promoted violent acts in the United States and elsewhere on behalf of ISIS. “Go on drive bys, and spill all of their blood, or rent a big truck and drive all over them. Veterans, Patriots, Memorial, etc. day… Kill them,” she tweeted.

Muthana is now living in a Kurdish displaced-persons camp in Syria where, she claims, she has seen the error of her ways and, on return, is willing to take her chances in a court of law. Thirteen other foreign fighters from the US have already returned home to face trial. In denying her citizenship, however, the Trump administration is obviously using a distinctly unpopular figure, a willing former Islamist terrorist, to strike at the very heart of the idea of citizenship. Depending on how her case is decided in courts that are increasingly filled with judges chosen by President Trump, it could change the way the government handles citizenship for the US-born; and as citizens are at the top of the pyramid, it could strike yet a stronger blow against those with lesser guarantees under the law who are now distinctly in Donald Trump’s sights.

Muthana does not hold dual nationality, which means that any withdrawal of her citizenship would actually violate international law, as the Geneva Conventions specify that no person can be rendered stateless by the revocation of his or her citizenship.

In other words, the attempt to block Hoda Muthana’s return represents a potentially giant step by the Trump administration, setting a precedent that could weaken the formerly sacrosanct idea of citizenship in the United States. Consider this the ultimate slippery slope, one that could, over time, transform both the image, and the reality, of what it means to be an American.

Will the Statue of Liberty Be Denied Citizenship?

Halfway through Trump’s presidency, his administration has also moved to use citizenship as an exclusionary factor in other ways, continuing to craft a new, ever-more-restrictive vision of what it means to be an American. His team has proposed, for example, adding a “citizenship” question to the US Census, taken every 10 years, in hopes of depressing the count of immigrants who are not yet citizens. That, in turn, could change the way political power and federal funding are distributed, reducing voting rights and potentially the number of congressional representatives in a handful of key states, including Arizona, California, Florida, Illinois, New York, and Texas, where the majority of undocumented immigrants reside.

Sued for this proposal on constitutional and procedural grounds, the government lost at the district level in federal court. As US District Court Judge Jesse Furman stated, the attempt to add the citizenship question was “arbitrary and capricious,” as well as “unlawful for a multitude of independent reasons.” Moreover, Furman said, Commerce Secretary Wilbur Ross and his aides “tried to avoid disclosure of, if not conceal, the real timing and the real reasons for the decision to add the citizenship question.” (The Supreme Court is scheduled to hear the case during its spring 2019 term.)

The United States is hardly alone in reconsidering the nature of citizenship in a world where the populist right is obviously on the rise, at least not when it comes to those foreign fighters for ISIS. The German government recently decided that such fighters with dual citizenship will, in the future, lose their German citizenship. New Zealand has agreed to take back an ISIS fighter, recognizing that rendering a person stateless is a violation of the Geneva Conventions. Great Britain has stripped citizenship from several individuals accused of terrorism or ISIS affiliations, something at least theoretically permissible under the law there (as it is not in the United States). And Belgium just decided to revoke the citizenship of two women who joined the Islamic State, while accepting the citizenship of their six children.

In several countries, the conversation is not limited to foreign fighters. A report by the Center for Migration Studies, for instance, concludes that recent actions taken by the Australian, Canadian, and British governments illustrate a troubling expansion of a trend in which the revocation of citizenship is a response to transnational terror threats.

In its urge to build walls of every sort, seen and unseen, however, the Trump administration has taken the global lead in creating a world in which citizenship will be ever more narrowly defined. The Statue of Liberty has stood in New York harbor for well over a century. If President Trump succeeds in his assault on citizenship as an inclusive, irremovable right, then Lady Liberty will find herself, like Ellis Island, a mere reminder of another world, of a lost America, a country that once was a beacon of hope for those fleeing oppression. Perhaps it will even be sent back to France.