Hence, over the much longer term, a prolonged draught will kill all of the elephants because any sporadic intermediate rain will not be enough to keep them alive. However, only a few tiny sprinkles will be enough to allow the smallest life-forms to quickly reproduce that a few might survive to the next sprinkle. History teaches the same social lessons for the same reasons. Big complicated societies require large volumes of energy that is sustained and reliable. Temporary shortages can be endured, but prolonged cut-offs cannot be survived without contraction or collapse.
Human societies grow in population and complexity to the limit of their energy supply.
Once at that limit, system stability becomes precarious and breakdowns more frequent, insofar as the core energy supply may fluctuate due to external forces. When and as our OWN global system collapses various social movements led by charismatic individuals will doubtless claim credit in various places and triumphantly announce the dawn of some new era, but their effective control will be limited by the energy available to them at that moment, which by definition will be declining into micro-fiefdoms. I would imagine that by then we will again be out of contact, mutually isolated by the oceans that have trapped so many of us for so long. Shipping will doubtless continue, but I rather doubt that we will be able to hang onto the vast satellite and cable arrays that now make communication so easy. Lest any of you find my pessimism unrealistic, I remind you that empires collapse in their peripheries first, with the core yielding last.