Shortly after the Supreme Court announced in April that it would consider the nationwide freeze on President Trump’s executive order ending birthright citizenship, he gleefully spoke to reporters in the Oval Office.
Mr. Trump said that he was “so happy” the justices would take up the citizenship issue because it had been “so misunderstood.” The 14th Amendment, he said — long held to grant citizenship to anyone born in the United States — is actually “about slavery.”
“That’s not about tourists coming in and touching a piece of sand and then all of the sudden there’s citizenship,” Mr. Trump said, adding, “That is all about slavery.”
For more than a century, most scholars and the courts have agreed that though the 14th Amendment was added to the Constitution after the Civil War, it was not, in fact, all about slavery. Instead, courts have held that the amendment extended citizenship not just to the children of former slaves but also to babies born within the borders of the United States.
The notion that the amendment might not do so was once considered an unorthodox theory, promoted by an obscure California law professor named John Eastman and his colleagues at the Claremont Institute, a conservative think tank — the same professor who would later provide Mr. Trump with legal arguments he used to try to overturn the results of the 2020 presidential election.
The story of how the theory moved from the far edges of academia to the Oval Office and, on Thursday, to the Supreme Court, offers insight into how Mr. Trump has popularized legal theories once considered unthinkable to justify his immigration policies.
