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concepts out there that have little to no practical use (say, an anthem, or a motto), I'm just saying that your list outdated concepts were not good examples.