Dred Scott was born into slavery in 1795 and lived as a slave in Missouri. His owner, a military man named Emerson, took Scott with him when he was transferred first to Illinois and later to the Wisconsin Territory, neither of which had slavery. As a result of several moves, Scott ended up back in the slave state of Missouri. After Emerson died, his brother-in-law Sanford, who lived in New York, assumed control of his property, and Scott sued for his freedom in New York federal court.

The Founding Fathers believed citizens from another state might not get a fair shake in a state court subject to local bias. So they included the “diversity of citizenship” clause in the Constitution, which permits an out-of-state citizen to have his legal grievance heard in federal court. That clause was the basis for Scott’s choice of the federal court in New York.

In 1857, the Supreme Court decided Scott v. Sandford – the court documents misspelled Sanford’s name – generally considered the worst decision the Court has ever made. According to Chief Justice Roger Taney, whose name has become synonymous with the Dred Scott case, Scott had no right to sue in federal court because “a negro, whose ancestors were imported into [the U.S.], and sold as slaves … could not be an American citizen.” Taney went so far as to describe black Africans brought here as slaves as “beings of an inferior order … unfit to associate with the white race.”

Frederick Douglass, himself a former slave and a leader of the abolitionist movement, was undaunted. The “highest authority” had spoken, he acknowledged, but he was optimistic that the “National Conscience” would not, in his words, be “put to sleep.”

He was correct, though it took a Civil War, the Civil Rights Act of 1866, and a constitutional amendment to right the Supreme Court’s wrong. The Fourteenth Amendment, approved by New Hampshire in 1866 (the second state to do so) and ultimately ratified in 1868, overruled the Dred Scott decision. It says, “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.”

Dred Scott may be a familiar name in American history, but Wong Kim Ark is not. In the case that bears his name, the Supreme Court described his parents as “persons of Chinese descent,” aliens living in California who remained “subjects of the Emperor of China.” The question before the Court in 1898 was whether their son, born in San Francisco in 1873, was an American citizen.

This was a time of strong anti-Chinese feelings, codified in the Chinese Exclusion Act of 1882. Wong Kim Ark was returning from his second visit to China to visit relatives, including his parents who had moved back, when customs officials barred him from getting off the boat in San Francisco Bay. The Chinese Benevolent Association had a prominent lawyer named Thomas Riordan on call, and he obtained a court order upholding Mr. Wong’s birthright citizenship. The government appealed. It argued that Wong Kim Ark was not a citizen but was, “by reason of his race, language, color and dress, a Chinese person,” adding that he was also “a laborer by occupation.”

The Court’s answer was that Mr. Wong was born on American soil and therefore he, and “all other persons of whatever race or color,” are in the “clear words” of the Fourteenth Amendment, entitled to “citizenship by birth.” To hold otherwise, the Court added, would be “to deny citizenship to thousands of persons of English, Scotch, Irish, German, or other European parentage” who have always been considered to be citizens. (That last group would include my father, born in Chelsea, Massachusetts in 1891, less than two years after my grandparents got off the boat.)

On October 29, President Trump announced that he will issue an executive order overruling the Wong Kim Ark case and repealing the birthright citizenship clause of the Fourteenth Amendment. He didn’t put it that way, of course. He simply said that no other country makes you a citizen just because you’re born here, which is incorrect. Canada and Mexico, and many other countries, grant automatic birthright citizenship. According to Trump, “It’s ridiculous and it has to end.”

Those who agree with him point out, correctly, that when Wong Kim Ark was born, his parents were in this country legally. And they argue that the Fourteenth Amendment words “and subject to the jurisdiction thereof” refer to parents whose “allegiance” is to another country.

Neither of those arguments holds water. The Supreme Court made no distinction between parents here legally and those who were undocumented, and in any case all such parents are “subject to the jurisdiction” of the United States, including American courts. Those words refer to foreign diplomats and Native Americans, whose exclusion from birthright citizenship was cured by the Indian Citizenship Act of 1924.

I doubt that Trump will attempt to carry out his threat to turn the clock back and de-citizenize millions of Americans. That is not to say that the rules of citizenship cannot be changed. There is a way to do that. It’s called amending the Constitution, a prerogative that Article V grants to two-thirds of both houses of Congress, or to two-thirds of the states, subject to ratification by three-fourths of the state legislatures. Article V does not mention the President.

Somehow, I don’t think that’s likely to happen.