If you think the attacks on birthright citizenship led by our ignoramus-in-chief are just a midterm issue, think again. Beneath the bluster, the attacks are a rallying cry for voter suppression and will in all likelihood accelerate as the 2020 presidential race begins in earnest.

The attacks, moreover, are nothing new. They did not originate with Donald Trump.

Dissatisfaction with the principle that anyone born on American soil is automatically a citizen is as old as the 14th Amendment itself, in which the principle is inscribed. In calling for an end to birthright citizenship during the stretch run to the midterm elections, Trump is both reviving a campaign pledge he had made during his successful run for president and resuscitating the deep nativist currents of our political culture that had subsided—but never died—in the aftermath of the civil rights movement.

Trump began his assault on birthright citizenship at an Aug. 19, 2015, town meeting in Derry, N.H., when he told a crowd of ardent supporters that “many of the great scholars say that anchor babies [the derogatory term for the children of undocumented immigrants who are born in the U.S.] are not covered” by the 14th Amendment. “We’re going to have to find out” by means of a court challenge, he said. The only difference between then and now is that Trump currently proposes to end birthright citizenship by executive order.

To understand the attacks and the fringe scholarship that undergirds them, it’s necessary to recall the origins of the 14th Amendment, and in particular, the first sentence of the initial section of the amendment—known as the “citizenship clause”—that reads:

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.

Like the 13th Amendment, which outlawed slavery, and the 15th, which guaranteed the right to vote, the 14th Amendment was adopted to overturn the Supreme Court’s infamous Dred Scott decision of 1857, which invalidated the Missouri Compromise and held that African-Americans, whether enslaved or freed, could never be U.S. citizens.

Together, the three amendments effectively returned the U.S. to the English common law practice of jus solis (the “law of the soil’’)—the idea that all those born within the geographic boundaries of a nation are citizens at birth. More than 30 countries today recognize the doctrine, including the United States, Canada and Mexico.

Both sides in the current birthright debate agree the 14th Amendment’s central purpose was to confer citizenship upon newly emancipated slaves. They also agree the amendment’s citizenship clause excludes children born to foreign diplomats and children born to enemy forces engaged in the hostile occupation of U.S. territory. They agree further the citizenship clause, as originally drafted, excluded Native American children because they owed their allegiance to tribal nations that had their own reservations. (Native Americans were finally granted citizenship with the passage of the Indian Citizenship Act of 1924.)

However, when it comes to the offspring of the undocumented, the two sides disagree sharply over the meaning and purpose of the citizenship clause’s language limiting citizenship to people “subject to the jurisdiction” of the U.S. Those who align with Trump maintain the clause pertains only to those who declare unswerving allegiance to America and no other sovereign nation. Those who believe the president is wrong maintain that the disputed language means citizenship is accorded to all persons (except the children of diplomats and occupying enemy forces) born or naturalized in the U.S. who are subject to the authority of American law.

The scholars to whom Trump has referred to bolster his birthright attacks are a distinct minority, but they include some prominent names in conservative legal circles. They include law professors Peter Schuck of Yale and John Eastman of Chapman University, as well as 7th U.S. Circuit Court of Appeals Judge Richard Posner, all of whom have been writing on the subject for years. More recently, they have been joined by former Trump administration national security adviser Michael Anton, who wrote an op-ed for The Washington Post in July, and Andrew McCarthy, a National Review contributing editor, who pleaded his case in an essay last week.

Styling themselves as “originalists” faithful to the intended meaning of the citizenship clause, the outliers base much of their argument on the Senate debate on the clause, which was held on May 30, 1866, and was reported in the Congressional Globe, the precursor of today’s Congressional Record. The conclusion the outliers draw from the debate, however, is anything but faithful to the Senate’s 1866 deliberations, taken as a whole.

The citizenship clause was introduced in the Senate by Jacob Howard of Michigan as an add-on to the initial draft of the 14th Amendment. In his introductory remarks, Howard noted the clause would not apply to the families of ambassadors or foreign ministers but would “include every other class of person.”

It is true, as the outliers argue, that the Senate in 1866 did not have modern-day undocumented aliens in mind when they debated the clause, as the nation did not pass its first immigration law until the enactment of the Chinese Exclusion Act of 1882. It is also true some senators expressed dissatisfaction with Howard’s understanding of the clause.

Nonetheless, as 5th Circuit Court of Appeals Judge James C. Ho noted in a 2006 essay titled “Defining ‘American’ ”:

This understanding was universally adopted by other Senators. Howard’s colleagues vigorously debated the wisdom of his amendment—indeed, some opposed it precisely because they opposed extending birthright citizenship to the children of aliens of different races. But no Senator disputed the meaning of the amendment with respect to alien children.”

Ho is a lifelong Republican, who once served as the solicitor general of Texas. He was, ironically, appointed to the 5th Circuit by Trump this past January.

The Supreme Court has endorsed Howard’s reading of the citizenship clause in at least four decisions: United States v. Wong Kim Ark (1898), dealing with the readmission into the country of a Chinese man whom the government sought to exclude because he had been born in the U.S. to resident alien parents; Plyer v. Doe (1982), concerning the right of undocumented children to attend public schools; INS v. Rios-Pineda (1985), a deportation proceeding; and Hamdi v. Rumsfeld (2004), in which the court’s plurality opinion noted that a Guantanamo Bay inmate held as an “enemy combatant” was still a citizen because he was born in Louisiana.

Despite the clear and unambiguous judicial history supporting birthright citizenship, the outliers remain undeterred. In 1991, former House Republican Elton Gallegly introduced a bill that sought to establish that only children born to legal residents could be accorded citizenship. Although the legislation never made it out of committee, The Guardian has reported that similar measures have been introduced in each succeeding session of Congress. As a congressman, Vice President Mike Pence was a sponsor of an anti-birthright law proposed in 2009.

Shamefully, over the years, even some Democrats have hopped on the anti-birthright bandwagon. In 1993, for example, then-Nevada Sen. Harry Reid introduced the Immigration Stabilization Act of 1993, which would have nullified the citizenship clause.

“If making it easy to be an illegal alien isn’t enough, how about offering a reward to be an illegal immigrant. No sane country would do that, right?” Reid, a Democrat, asked his colleagues during a floor speech on Sept. 20, 1993. “Guess again,” he continued. “If you break our laws by entering this country without permission and give birth to a child, we reward that child with U.S. citizenship and guarantee a full access to all public and social services this society provides—and that’s a lot of services.”

Reid’s bill failed to pass.

Even if all the current executive, congressional and legal attacks on birthright citizenship run aground as they should, given the plain text of the 14th Amendment, the attacks will continue, and for good reason: In the hands of Trump, the attacks are a sound organizing tactic. They “rile up the crazies” in Trump’s base and help secure fealty to his leadership in much the same way as his calls to “open up the nation’s libel laws” and his castigation of the media as “fake news” arouse his supporters.

The actual number of “anchor babies” born in the U.S. is uncertain. According to the Pew Research Center, however, “about 275,000 babies were born to unauthorized-immigrant parents in 2014, or about 7 percent of the 4 million births in the U.S. that year.” In Trump’s universe, they will all grow up to vote Democratic. Hence, the need to suppress their voting rights or dilute their voting power, if not entirely, then piecemeal by lesser means, such as restrictive voter ID laws and political gerrymandering.

And though the odds are long, it’s always possible the Supreme Court, now dominated by conservative justices affiliated with the Federalist Society, could one day disregard past precedent and overturn birthright citizenship altogether for undocumented newborns. Such an about-face would deliver a mother lode of future voter suppression, and from the Trumpian perspective, truly make America “great”—read white—again.