President Donald Trump’s suggestion in an interview with Axios that he is considering an executive order to “terminate” birthright citizenship should be seen for what it is — a laughable, legally frivolous proposal designed to do little more than energize his base and distract his critics one week before the midterms.

It’s not that there aren’t serious debates to have about the theory of birthright citizenship; it’s that, as a matter of constitutional interpretation, the issue has been settled by the Supreme Court since 1898. If Trump really wanted to change this longstanding and well-settled rule of American constitutional law, the proper way to do so is to propose a constitutional amendment, not a unilateral diktat.

It’s not that there aren’t serious debates to have about the theory of birthright citizenship; it’s that the issue has been settled by the Supreme Court since 1898.

The Constitution recognizes the principle of birthright citizenship principally through the Citizenship Clause of the 14th Amendment: “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.” Ratified shortly after the end of the Civil War, the Citizenship Clause was meant to overrule the Supreme Court’s 1857 decision in the Dred Scott case, in which the court had infamously ruled that slaves and their descendants were not, and could not be, citizens of the United States. By its plain terms, those both born in the United States and subject to its jurisdiction are citizens, full stop.

Recently, some commentators have seized upon the “subject to the jurisdiction thereof” language to argue that, in fact, the Citizenship Clause only applies to those who have lawful immigration status — and so excludes children born on U.S. soil to undocumented immigrants. As Fifth Circuit Judge James Ho (appointed by Trump) wrote in a 2006 essay, this argument cannot be reconciled with either the text or the original understanding of the Citizenship Clause, which confirms that it “plainly guarantees birthright citizenship to the U.S.-born children of all persons subject to U.S. sovereign authority and laws.”

And even if Trump disagrees with his own appointee, the Supreme Court has repeatedly reached the same conclusion.

In its 1898 ruling in United States v. Wong Kim Ark, for example, the Supreme Court explained that the “real object” of the “subject to the jurisdiction thereof” language was to exclude from its coverage exactly three classes of individuals: children of Native American tribes born on reservations “standing in a peculiar relation to the National Government;” “children born of alien enemies in hostile occupation” during wartime; and “children of diplomatic representatives of a foreign State.” That was it. Otherwise, anyone born on U.S. soil was entitled to birthright citizenship regardless of how they got there.

The Wong Kim Ark case is not a dusty, antiquated relic. In 1982, the Supreme Court not only reaffirmed its holding, but made express what it had held implicitly — that the Citizenship Clause therefore applies to children of undocumented immigrants, as well. As the court explained, “no plausible distinction with respect to Fourteenth Amendment ‘jurisdiction’ can be drawn between resident aliens whose entry into the United States was lawful, and resident aliens whose entry was unlawful.” And three years later, the court was even more explicit. Referring to the married, undocumented immigrants at issue in that case, the court noted that they “had given birth to a child, who, born in the United States, was a citizen of the country.”

Don’t get me wrong: Trump (and others) may well disagree with this unbroken line of Supreme Court decisions interpreting the Citizenship Clause — and the broad principle of birthright citizenship for which they stand. My own view is that the court got it right, but it’s certainly their prerogative to dissent.

The relevant point for present purposes is that, as the Justice Department’s Office of Legal Counsel concluded in 1995, the Supreme Court has clearly and specifically addressed the issue — and thus there is no reasonable way to argue that the Supreme Court’s consistent interpretation of this constitutional text could be overridden by a statute (let alone by an Executive Order). As Judge Ho concluded in his 2006 essay, “a constitutional amendment is... the only way to restrict birthright citizenship.”

Of course, Trump (or, at least, his lawyers) knows this. And while many Americans view the current Supreme Court with cynicism, this is a line of precedent that is more or less invulnerable. As Judge Ho demonstrates, even on a blank slate, conservative jurists are highly unlikely to rule in Trump’s favor, were he to press the issue.

What this analysis suggests is that this is not a serious proposal — and we will likely never see the promised executive order. Instead, once again, the president is stirring up a frenzy — exciting the more nationalistic members of his base while also infuriating his critics. That may make for good politics, but it’s pretty bad — indeed, indefensible — as constitutional law.