“Whether this is a war or there’s an invasion is going to be subject to litigation, and there is good law on the side against the president on this,” said Muzaffar Chishti, a senior fellow at the nonpartisan Migration Policy Institute.

The 14th Amendment to the Constitution — ratified in 1868 — 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.”

Trump’s order, one of many he signed following his inauguration Monday, did just that, arguing that the 14th Amendment “has never been interpreted to extend citizenship universally to everyone born within the United States,” and “has always excluded from birthright citizenship persons who were born in the United States but not ‘subject to the jurisdiction thereof.’”

Trump attempts to get around this plain meaning by latching onto the words “subject to the jurisdiction thereof.”

His order claims that the children of immigrants are not “subject to” the United States’ jurisdiction, presumably because their parents are citizens of another country.