

They’re doing this because success would set up factual predicates to support invoking the Insurrection Act. The Insurrection Act is invokable when state governments are actively disobeying federal law.
They’re not invoking the Insurrection Act right at this moment, because with the facts they have right now, they’re not confident they’ll win the case in court. (And they may also lose a voting majority in Congress on the matter.)






The active duty marines did actually detain a civilian Angeleno before that situation was shut down.
Edit: Part of the legal difficulty is that Posse Comitatus Act violations are written up as crimes in the statute. It’s not clear that someone could actually sue to enforce with a civil lawsuit. And good luck getting DOJ to file charges on that.