The Supreme Court Remembers Its Principles

The Supreme Court's decision on Tuesday to preserve birthright citizenship comes as a relief. President Trump's unilateral effort to prevent the children of undocumented immigrants from automatically becoming citizens was plainly unconstitutional. His executive order violated the 14th Amendment, which declares in its opening sentence, "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."

Mr. Trump's case rested on the phrase "subject to the jurisdiction thereof," with his lawyers claiming that the children of parents who came to this country illegally were not subject to the jurisdiction of the U.S. government. But as the majority opinion by Chief Justice John Roberts shows, the history of the citizenship clause of the 14th Amendment, ratified in 1868, makes clear that "subject to the jurisdiction" refers to the power of the United States to govern people within its territory. Federal and state laws do, of course, apply to the children of migrants. They are not diplomats with immunity.