Just as WWIII, the civil war is already well under way. Warfighting tech and sophistication has com a long way since John Brown.
Well, the civil war really started with Bleeding Kansas and the KS/MO borderwars, that was about 6 years before Ft Sumner? (1854; Attack on Ft. Sumner was 1861) I would say that it began in 2016, when Trump was elected and the DS reacted.
(Did you have salmon for dinner? Or Halibut? :)