Well. If there’s nothing identifying them as an arm of the state, it’s legal to shoot them in self defense should they try to kidnap you. You can also say that the law doesn’t matter anymore as the US government is flagrantly violating it but that also means that the law no longer has legitimacy as the government is breaking it’s end of the social contract. Therefore, normal morality in the absence of law applies which says that self defense is legitimate.

Maybe it’s worth buying a gun and learning how to use it so that, if they come for you, you at least get to kill a fascist.

This could be the only thing that would deter them.