Jim Mone / AP

When Representative Ilhan Omar recently complained about “the political influence in this country that says it is okay to push for allegiance to a foreign country,” many noted accurately that she had deployed a trope—dual loyalty—that had been used against Jews for years.

But this accusation has a broader history in the United States, having been used against several religious minorities—including Muslims like Omar. Indeed, many battles over religious freedom have revolved around dual-loyalty claims.

In the 19th century, many attacks on Catholics stressed that these immigrants were pawns of a foreign power. In the 1830s, Samuel Morse—then a prominent painter and later the inventor of the telegraph—urged Americans to build “walls” and “gates” to keep out Catholic immigrants, who would always be loyal to Rome. Because these Catholic immigrants were decrepit—“halt, and blind, and naked”—they were easy to control. With their “darkened intellects,” they “obey their priests as demigods.” The Vatican could deploy these “senseless machines” to seize power in America.

When Al Smith, a Catholic, ran for president in 1928, he faced constant charges that he was the puppet of Rome. A picture of the recently built Holland Tunnel in New York City was used to suggest that he would extend it all the way from America to the Vatican. One editorial cartoon depicted him as a busboy serving liquor to bishops.

Smith sometimes tried to deflect the charges with humor. When challenged with the content of a papal encyclical that was supposedly incompatible with American democracy and ostensibly would determine his decision making, he quipped, “Will somebody please tell me what in the hell an encyclical is?”

One of the most sophisticated expositions of the dual-loyalty argument happened in these very pages. In a 1927 article in The Atlantic, a Protestant lawyer named Charles C. Marshall cited various Vatican rulings to prove that Smith would have to defer to the pope: “Here arises the irrepressible conflict. Shall the State or the Roman Catholic Church determine [legal issues]? The Constitution of the United States clearly ordains that the State shall determine the question. The Roman Catholic Church demands for itself the sole right to determine it, and holds that [it is] superior to and supreme over the State.” Smith, he argued, would have to make decisions based on his loyalty to the Church.

Smith responded in The Atlantic with an essay of his own, arguing that the behavior of actual American Catholics bore no resemblance to the scare version conjured from bits of papal encyclicals or the dark chapters of European history. Most important, as governor of New York, he’d never had any trouble putting his loyalty to New Yorkers first. He made the point that was missing from so much of the anti-Catholic literature—and from modern-day discussions about Islam, Judaism, and other religions. American Catholics had the capacity to juggle their adherence to Church teachings with their love of country. “You seem to think that Catholics must be all alike in mind and in heart, as though they had been poured into and taken out of the same mould. You have no more right to ask me to defend as part of my faith every statement coming from a prelate than I should have to ask you to accept as an article of your religious faith every statement of an Episcopal bishop, or of your political faith every statement of a President of the United States. So little are these matters of the essence of my faith that I, a devout Catholic since childhood, never heard of them until I read your letter.”

In order to dispel the dual-loyalty charge, John F. Kennedy, in 1960, came out strongly for separation of Church and state. America’s approach to religious liberty guaranteed that dual allegiances could never get traction. “I believe in an America where the separation of Church and state is absolute, where no Catholic prelate would tell the president (should he be Catholic) how to act, and no Protestant minister would tell his parishioners for whom to vote,” Kennedy declared. The First Amendment ensured that Kennedy would never be tempted to put his faith over his country.

The dual-allegiance charge against Jews was enshrined in the most notorious anti-Semitic document, the Protocols of the Elders of Zion, which claimed that Jews would always place the interests of world Jewry over that of their host country. After the birth of Israel, Jews were sometimes accused of putting Israel’s interests before America’s, such as when some critics of the Iraq War suggested that Jewish neoconservatives were pushing the nation into a foolish conflict to advance Israel’s foreign-policy goals. More recently, American Muslims have been most subject to the dual-loyalty charge, something that Omar, as a trailblazing Muslim woman, should consider.

In the case of Muslims, the slander has come in the form of the campaign against Sharia, the broad body of Islamic law. The anti-Sharia efforts have maintained that American Muslims—like American Catholics—must abide by a foreign law created by a foreign religion in a foreign land. Brigitte Gabriel, the leader of ACT for America, has argued that if you’re a devout Muslim, you by definition cannot be a loyal American: “A practicing Muslim who believes the word of the Koran to be the word of Allah, who abides by Islam, who goes to mosque and prays every Friday, who prays five times a day—this practicing Muslim, who believes in the teachings of the Koran, cannot be a loyal citizen to the United States of America.”

Emphasizing the influence of the law enabled opponents to strip Islam of its legitimacy as a religion. “Islam is a political ideology … It definitely hides behind being a religion,” Michael Flynn, President Donald Trump’s first national security adviser, once said.

And being a political system—controlled from abroad—means it does not merit First Amendment protection. “Far from being entitled to the protections of our Constitution under the principle of freedom of religion,” declared a report by the Center for Security Policy, Sharia “is actually a seditious assault on our Constitution which we are obliged to prosecute, not protect.” Conservatives who criticize Omar for her divided-loyalty comments but then also support the anti-Sharia crusade are applying a double standard.

Of course, dual-loyalty slanders are usually constructed around an element of truth. American Jews often do support Israel, Catholics often follow the teachings of the Church on important issues, and Muslims do observe elements of Sharia at odds with majority culture (such as eating halal foods). It’s totally fair to point out that these religious minorities—like all other Americans—are subject to cross-pressures.

But dual-allegiance charges go much further than offering a polite disagreement on policy. They imply not only that a group is un-American, but that its adherents have no agency. They cannot be patriotic, because they are thoroughly under the influence of a foreign power or code. And when the spell is being cast by a religion, it is deemed an especially powerful form of mind control. If you’re a good Catholic, you have no choice but to follow the pope. If you’re a good Muslim, you have no choice but to follow Sharia (and therefore support terrorists).

The truth is that American Catholics, Muslims, and Jews have charted their own course, sometimes listening to guidance from abroad but more often ignoring it. Recently, a West Virginia Republican group put up a poster of Omar in front of an image of the smoldering Twin Towers. If this is not exactly a dual-loyalty claim, it is a close cousin: An American Muslim is really the same as a terrorist Muslim. They read from the same holy book, follow the same Sharia law, and certainly can’t be trusted to be loyal Americans. This is where the logic of divided loyalties—a logic Omar is herself applying to American Jews—ultimately leads.

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