Consensus produces power through the conservation of effort. It represents those things that we do not consider when we set out to solve a problem. So, for example, in America it is only the very few that envision changing government policy through armed revolt. This means that the states and federal government have a greatly reduced burden to protect public assets from destruction, as perhaps compared to the Congo. It also means that participants in public debate do not have to deal with overt threats of physical violence, nor invest substantial energy in planning to mitigate its consequences. If the two public sides in a zoning debate disagree, neither will have to plan to raise a militia to fight overt aggression. When overt threats of physical violence do arise, they occasion such outrage that the public willingly assists in apprehending and punishing the aggressors.
When these circumstances fail, on the other hand, every participant in decision-making must invest attention in unproductive contingency planning for violence. This is the cost imposed on society by terrorists, whether organized criminals, political dissidents or external enemies. There are a number of ways to fight such practices, but the reality is that any such battle involves casualties. The resolve that enables societies to successfully wage that war arises from a healthy spiritual dynamic, and will be addressed in that context.
Consensus also appears in technological circles. The design of retail space is an example. These are limited to certain forms that curtail the amount of effort invested in designing a new development. While this may result in suboptimal usage of space in many instances, the controlling benefit arises in the capacity of the industry to respond to demand, in part due to the cost and time savings of design reuse.
Every form of social power is contingent. By this, I mean that individuals will subscribe to the forms of power only in so long as they are allowed to prosper within that context. A useful observation on human nature, in this regard, is that people will change what they believe before they will change their behavior. If we assume that our behavior is impeccable, the only explanation for systemic failure is the confounding influence of our co-participants. Once we have abandoned our faith in others, renegotiation of behavioral norms (e.g. - establishing a new consensus) is so encumbered that it becomes almost unachievable.
Given the beneficial consequences of consensus, the primary responsibility of the social elite must be to focus its energy on ameliorating these kinds of crises. In turn, the populace needs mechanisms to starve the elite of power when it has lost the thread of their interests. Sometimes the only means available is to encourage social collapse - either actively, or through passive resistance. In ancient times, the transition was assisted by the intervention of barbarians. In modern times, the process of social evisceration would appear destined to follow a far longer arc. Better mechanisms must be found.