The Supreme Court is examining President Donald Trump’s executive order from Ja. 20, 2025. That order seeks to deny birthright citizenship to children born in the U.S. whose parents are in the country either illegally or on temporary visas.Lawfaremedia.com reports that despite a vast number of supporting briefs in Trump v. Barbara, one key issue that undermines Trump's order has not received enough attention. Author and professor of law at George Mason University Ilya Somin contends the government's position would override the central purpose of the Citizenship Clause of the Constittution's Fourteenth Amendment. “For that reason alone, the Trump Administration should lose the case,” he writes. The Citizenship Clause sought to grant citizenship to newly freed slaves and their descendants, a reversal of the 1857 Dred Scott decision. But all of the current administration's arguments would step on that. The Citizenship Clause states that “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.” The government's position in Barbara depends on the claim that children of undocumented migrants and temporary visa holders are not “subject to the jurisdiction” of the U.S. The simplest argument for the government's position is the idea that illegal entry somehow prevents undocumented migrants and their American-born children from being subject to U.S. jurisdiction. "This is extremely dubious," Somkin writes, "because undocumented migrants are undeniably subject to U.S. law. But, if the argument is valid, it would also have excluded large numbers of freed slaves and their descendants."Thus, “Any interpretation of the “subject to the jurisdiction” wording that requires denying birthright citizenship to large numbers of slaves and children thereof must be rejected, Somkin argues. Another standard argument for the administration's position is that illegal migrants, non-citizens on temporary visas, and their children lack the requisite exclusive “allegiance” to the United States. That’s because they still owe allegiance to their countries of origin. If, as this theory assumes, people owe allegiance to the government of the country they are born in, it obviously applies to virtually all freed slaves as well, even those brought into the U.S. legally.Somkin goes on to refute arguments on the status of Native Americans and the so-called “domicile” theory, which claims that children of undocumented immigrants are not subject to U.S. jurisdiction because their parents are not properly domiciled in the U.S.While there already exist exemptions to birthright citizenship - children of foreign diplomats and those born on foreign public ships in U.S. territorial waters are two examples - Somkin believes the link to slavery “provides a powerful additional rationale for ruling against the administration's position, one that negates every one of its arguments. All those theories are at odds with the main purpose of the Citizenship Clause and must be rejected for that reason alone."