Does the state exist? Yes. No amount of magic fairy dust throwing can change that short of a worldwide other throw of all governments simultaneously will change that.
Is the state doing the simplest thing (that I and others have suggested)? No.
So the only solution left is a statist one.
Does that track?
Yes. Thieves, rapists, and murderers are, in fact, thieves, rapists, and murders. Do you have an issue with that? A conviction comes after they are caught and brought to a modicum of justice. Do you not believe that billions have been defrauded from public coffers? That is widespread theft. Are you blind to increasing rates of sexual assault in areas with higher concentrations of migrants? Same with murder. Yeah... "Not all." But the ones that are are intentionally hidden and protected by people intent on subverting this country. (That's been stated explicitly in so many places by so many people, if you don't acknowledge that, you're just being obtuse.)
If we are speaking of Minneapolis, Somalia. Some SA countries, too. Or if they are rapists or murders, after a quick, thorough trial, a bullet in the back of the head is sufficient.
Yes. Currently. Does it have to be? No. I'd ratter it be handled by the individual states. But, again, it currently is in the court of the FedGov to enforce borders.
Yes, the same feds that let them all in. All of this is entirely arbitrary. But, technically, ICE is doing the job they are created for. Which is better than not. IMO.
Militias are a better option, I agree. No state has sacked up to do that yet. Do you think any will? No. Why? It endangers the local tyrants, too. So... Now what?