A federal government being willing to enforce the law Reconstruction style and send in federal troops to effect the arrest of these traitors and the unconditional surrender of their government. Anything less is just giving the anti-democratic forces time to get stronger and chip away at more of our society.
At first I was writing a comment to say the Posse Comitatus Act wouldn't allow this, but it seems like the Insurrection Act of 1807 is an exception, and would apply in this instance.
The President, by using the militia or the armed forces, or both, or by any other means, shall take such measures as he considers necessary to suppress, in a State, any insurrection, domestic violence, unlawful combination, or conspiracy, if it—
(1)so hinders the execution of the laws of that State, and of the United States within the State, that any part or class of its people is deprived of a right, privilege, immunity, or protection named in the Constitution and secured by law, and the constituted authorities of that State are unable, fail, or refuse to protect that right, privilege, or immunity, or to give that protection; or
(2)opposes or obstructs the execution of the laws of the United States or impedes the course of justice under those laws.
In any situation covered by clause (1), the State shall be considered to have denied the equal protection of the laws secured by the Constitution.
Edit: I feel compelled to point out that we're not here yet, because the SCOTUS order has a review process for the new voting maps, and if a judge rejects them, the judge can authorize a third party to draw the maps for Alabama. If the Alabama government rejects those third-party maps, then shit gets real.