I think what you're reading and registering is a clash between diehard party partisans . . . faction leaders . . . who have a difference in ideology but are still basically Americans merely shilling for their view of what America should be. Prager's admonission seems to me nothing more than an outline of his own political ideology, described as a polemic, not a roadmap towards certain civil war.
Political, legal, and societal remedies exist for all Prager's issues. Civil war occurs when those remedies are no longer available, or once one side determines the point of no return has been passed. I hardly see that dynamic in American politics today. If anything, the rhetoric from partisans has been amped up . . . and I daresay some, if not most, of that amplification is selfishly purposeful.
1. Additional geographic stratification (red zone / blue zone) Current trends have to continue so that states or regions are strongly self identified as "conservative" or "socialist" or "liberty" or whatever, and those who oppose these views are a small minority. Even the blue/red zones are not this way now. If you pushed the threshold for coloring in the map from 50% majority in county to 60% it would totally chnage it. If you imposed a 70% majority to color a state red the entire map would be blue. 2. One or more states disobeying the federal government. I think a State is the obvious unit for CW2 flash point. Until a State (or several) elect leaders who are anti-federal I think we have a long way to go. 3. "Lines in the Sand" are clearly drawn and understood. To some extent the 2nd Ammendment is already one such line. When new more explicit lines are drawn saying "we won't tolerate this" that is a big warning sign. Such things did take place at the start of CW1. 4. One or more political parties form with a focus on seccession or radial change. Not "reform". These parties attract 1 million or more members. 5. Military or militia units are formed outside the control of FedGov. These are large scale an include heavy arms. Tom Chittum's book has a bunch more, some of which I don't think are significant, some of which are.
Florida 2000 was just a hint of things to come, just a taste.