The ways that fear and stress shape cultures and nations may have corollary systems, symptoms and processes to those that haunt individual brains, personal experiences and memory. The amygdala hijack is in some places and at some times a distributed cultural phenomenon. Microcosm/macrocosm explanations are useful in this context but can be (and often are) misused.
Notice how symbolic (narrative, ideological, political) activity driven by (or for opportunistic reasons – driving towards) fear tends towards pathological assertions of certainty, structure and continuity. Observe also how assertions of continuity and certainty generate precisely that insecurity that they (claim to) seek to assuage. There is a recursively self-propagating information system at work in this, albeit experienced as cognition, self-identity or in language and cultural identity.
Is fear and anxiety a necessary component as paranoiac self-surveillance in individual or collective, tribal (and beyond) identity formation? Regardless, and at a broader cultural level, it seems that self-definitions gravitate and sediment more concretely around shared painful moments in history and there are quite solid existential, evolutionary reasons for this.