"It’s easy to imagine that a second civil war might proceed like the first: two institutionalized factions wielding state militaries against each other along prescribed strategic fronts. Generals would choose a side, those with the most troops and firepower at their disposal would claim victory. The outcome, we imagine, would likely be a winner-take-all restructuring of the United States. But that’s not really how wars are fought in the 21st century. Indeed, much of the last century was about deconstructing the habits of large-scale, state-driven conventional warfare. As networks distribute power to the edges, warfighting shifts further away from a handful of monolithic forces and towards a diverse web of small actors. Warfare now often proceeds from ideologically and economically marginalized communities whose suffering and fear is wielded by cunning global actors. They become guerrillas, rebel factions, proxies, and insurgencies. Sometimes they look more like tribal conflicts composed along racial, religious, familial or economic lines, often on top of resource crises that push violence to become a necessary solution. But they are rarely simple two-sided conflicts."