Automation might be viable in some places in the Americas where cartels effectivley have full control over a region, or for anyone else in a sufficiently remote region who wants to achieve something simialr. Everywhere else you would want to choose your targets carefully. It's easier for police to turn a blind eye if you don't appear to be waging war against them.
Thats were you wrong, that a faction has to be defined to wage a war. Its just another city were some unknown party carried solar charged boxes on the roof, that dislodge drones on siren sound or whatever. The idea, that there is a "war" declaration or even somebody there, is part of the past.
You could hire gig workers to place the dronepackages a "pr" gag allover town. There is not a need for flags, territory or other outdated concepts. Just attrition and correlation.. of wear and tear on civilization
"There is not a need for flags, territory or other outdated concepts."
Any conflict has reasons behind it, as it is just another enterprise that consumes resources for expected rewards. Given the practical needs to manage the said consumed resources, even in guerilla style warfare the conflicts have to have limits (i.e. be contained to a territory). The territory, which these conflicts are waged on, can be and is sooner or later linked to (at least suspected) interested parties. The flags are basically just means to identify a given interested party once it grows past the Dunbar’s number. I do not say that there aren't concepts out there that have little to no practical use (say, an anthem, or a motto), I'm just saying that your list outdated concepts were not good examples.
The reason being that non-state actors, who want to become state actors thrive in a chaotic environment. Coporations and non suit wearing gangsters who can rely on there own power monopolies as long as they are unchallenged by the state, might push such a environment via third parties, to be "left alone".
