The Citizenship Clause, ratified in 1868 after the Civil War, was included to ensure that formerly enslaved people would be citizens. It effectively overturned the notorious Dred Scott decision, in which the Supreme Court held that Black people, no matter their status, were not citizens.

A case focused on birthright citizenship could come later, but the bulk of the argument is expected to concern whether a single judge can freeze a policy nationwide.

The Supreme Court is hearing arguments this morning on what’s outwardly a case about President Donald Trump’s attempt to restrict... Thomas opens the arguments asking for a historical analogue to universal injunctions.