There are 2 links in this note to the work of David Betz a professor of war studies in England who has been very public about his expectations of Civil War in recent years. His first article and his best interview imo.
He puts England and France as most likely to be the first to flare up. He says it will likely take the tone of a Latin American style Dirty war, early on, of assassinations, intercommunal conflict, kidnapping which later develops into a conflict between the rural and the urban, with systems disruption being a dominant theme. Erik Prince has also alluded to a rural/urban theme FWIW.
Highly recommend you familiarize yourself with his perspective.
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