From what?
How? By states? By counties? By cities? By districts within cities? By political affiliation? By ideological persuasion?
Then what? How do you keep the leftists from moving in anyway? That is what they have done in CO, ID, NM, etc. Barriers? Walls around states?
Passports to get from MO to IL, etc.?
These secessionist entities need a lot more planning and explanations of who they are, what they intend, and how they expect to get there.
Then what? How do you keep the leftists from moving in anyway?
That’s what independent countries do! They don’t give visitors voting rights.