Immigrants take the oath of allegiance during a naturalization ceremony in September in Jersey City, New Jersey.Drew Angerer / Getty Images

At the end of the naturalization process, all immigrants are required to take a public oath of allegiance—not to the president, or even to the United States per se, but to the Constitution. It’s an act few native-born Americans ever consciously perform: publicly and patriotically affirming the nation’s founding charter.

This act represents a kind of “constitutional patriotism.” In the absence of any shared ethnic, religious, or cultural heritage, newly minted citizens pledge fealty to the abstract concepts of liberty, equality, and justice for all. They are, in theory, forced to confront and internalize these fundamental values. In the process, they sometimes come to know the country better than those who wave the flag the hardest.

There are many immigrants willing to take that pledge. The last three months of 2016 saw a 28 percent increase in the number of naturalization applicants compared with the last three months of 2015. As some news reports suggested, one reason for the uptick may have been fear of Donald Trump’s stricter tact on immigration. There are deeper cultural dynamics at play, too. The country is riding a new wave of the nativism that has intermittently characterized much of American history, from the anti-Catholic Know Nothings to the Chinese Exclusion Act, to anti-Irish, -Italian, -Jewish, -Catholic, and -Japanese animus, to the two chief targets du jour: Muslims and Latinos. Although green-card holders have greater due-process protections than other non-citizens, the only true shield from deportation is a naturalization certificate.

The oath is striking for the way it eschews the cultural nationalism so loudly trumpeted by the America First crowd, by putting devotion to the Constitution above all else: “I hereby declare, on oath … that I will support and defend the Constitution and laws of the United States of America against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same.” This distinction is critical: It is only the Constitution’s enemies the new American must vigorously oppose, perhaps by taking up arms, but also at the ballot box. In other words, the naturalized citizen promises loyalty to the foundational ideas underpinning America, not to any one group of Americans.

The oath requirement is nearly as old as the Constitution itself. The first naturalization law, passed in 1790, permitted any free, white person who had lived in the United States for two years to petition a court to become a U.S. citizen. Before it could be made official, the petitioner needed to show proof of good character and pledge to support the Constitution. An officially scripted version of the oath did not appear until 1929. In the early 1950s, Congress added additional provisions requiring an applicant to declare their willingness to bear arms and to engage in noncombatant service in the armed forces on behalf of the United States. These two Cold War additions are the last major updates to a tradition that has now lasted almost 227 years. They can be deleted from the oath if an applicant is a religious or conscientious objector; the pledge to support the Constitution, however, is non-negotiable.

In taking the oath, new citizens are asked to honor the nation’s principles without many specific constraints. Their patriotism becomes linked to universal values that can be contested and interpreted in different ways, but do not depend on any monolithic version of Americanness. Abdul El-Sayed, a candidate in Michigan’s 2018 gubernatorial race, described this relationship to America as many immigrants before him have: “My dad, he immigrated from Egypt, and he was looking for an America that was big enough for him, too. He chose to come here because he knew he could raise his children to practice [their faith] as they wanted and be just as American as anyone else.”

A poster that’s dotted protest crowds since Trump’s inauguration captures the qualities of immigrants’ constitutional patriotism well: Shepard Fairey’s rendering of a young woman draped in a hijab made from the American flag. Partially an allegorical figure, a 21st century Lady Liberty, the image appropriates constitutional language and redeploys it for a multi-colored, multi-sectarian America. It’s based on photographer Ridwan Adhami’s decade-old portrait of Munira Ahmed, who like Adhami is a Muslim American from Queens. Both images suggest that immigrants like Ahmed have just as much claim to the symbols and rhetoric of patriotism as others. The “We the People” inscribed in Fairey’s illustration includes not just the flawed but visionary Americans of 1789, but also the millions who came after.

When it comes to immigrant patriotism, the tough part to disentangle is whether messages like this are actually a subtle overcorrection, a political sign born out of the anxiety of not being perceived as patriotic enough. The video of Khizr Khan, the father of slain U.S. Army Captain Humayun Khan, dressing down Trump at the Democratic National Convention perhaps suggests a similar dynamic. “Let me ask you,” Khan demanded, his voice rising, “have you even read the United States Constitution? I will gladly lend you my copy.” Khan’s speech could be more optimistically read as analogous to the naturalization oath, a symbolic act showing how voluntary Americans can and often do understand the Constitution better because they are forced to grapple with its meaning. (They know their civics, too: A 2012 study found that only a third of native-born Americans could pass the naturalization civics test, while 97 percent of immigrant applicants do.)

Constitutional patriotism is in some ways a peculiarly American concept—one that would seem to be an inherent part of the country’s democratic experience rather than an adoptable philosophy. But it has influenced how other democracies have envisioned citizens’ relationship to the state. For example, Germany, too, requires an oath to its constitution for naturalization: In English, “I solemnly declare that I will respect and observe the Basic Law and the laws of the Federal Republic of Germany, and that I will refrain from any activity which might cause it harm.”

The German oath tracks a remarkable period of political reflection in post-war Germany. As Princeton political-science professor Jan-Werner Müller described in Constitutional Patriotism, after the war, West German intellectuals were deeply concerned with how to bind together a half-nation scarred by the legacy of Nazism’s ethnic nationalism and the failure of Weimar’s liberal democratic order to prevent it. They considered how the state could embody universal principles—democracy, equality, anti-totalitarianism—while still commanding the loyalty of its citizens.

In 1979, one such intellectual, Dolf Sternberger, popularized the term Verfassungspatriotismus, or “constitutional patriotism,” to describe a relationship to the state similar to the one American immigrants have, one in which citizens feel loyalty neither to an ethno-centric homeland nor to a post-national global order, but to specific moral and legal principles. By reflecting together on both the horrors of Nazism and the liberal values built into the postwar constitution, West Germans could achieve a new kind of belonging. One could be patriotic without jingoism, without chauvinism, without hate. Individuals could become “German” insofar as they adopted the country’s values of democratic rule and individual freedom embodied in the country’s constitution.

The development of German constitutional patriotism offers clues to understanding the purpose of the American naturalization oath. It’s one that implicitly asks immigrants to embrace the dark periods of American history that are woven into the founding text, as well as the amendments passed to rectify them. Just as centuries of Americans have changed the Constitution to hew closer to its ideals, immigrants have deepened the meaning of the oath. What began as the final test to becoming an American has become a democratic ritual of its own.

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