IMNSHO it will start when some probably right-wing extremists show that they can wrest the "monopoly on violence" away from some police department in order to impose their own rule on some citizenry somewhere. That's as opposed to simply using the police to do the same thing while they "serve and protect" the Masters Of The Universe.
It will be a battle for control over the forces of evil on the right. It will be a civil war I can live with. Us lefties can shoot at both sides. Watch out for the crossfire. Heh.
Think I'm kidding?
The 11 craziest things in Rick Perry’s ‘Fed Up’ manifesto
1. Wresting power back from the federal government is the battle of our time.
I rest my case.