It seems an unfortunate situation today that simple facts get lost in political rhetoric. But simple facts are simple facts.
Sustainability = Survivability
At the end of the day, sustainability equates to survivability. Most of the ancient “disappeared” societies in fact vanished because they failed to practice sustainability.
Some of the best examples to study are societies that lived on islands or in remote areas making mass migration, after the destruction of their environment, impossible. An island or an isolated area, by nature, has a limited set of available resources that are required for survival. If those critical resources are depleted or damaged beyond timely repair, survival becomes impossible. If that point is not plainly clear, then history is replete with examples proving it.
Many of the various unsustainable practices of ancient societies were related to factors such as deforestation (eliminating the source of fuel and construction materials), poor soils management resulting in depletion of nutrients by over-farming or erosion (which also polluted rivers and steams reducing critically important fish-stocks), overfishing resulting in fewer food sources, poor water management leading to shortages of usable clean water, and more recently, introduction of environmentally damaging non-native species.
Resources DO Run Out!
Critical non-renewable resources will run out…one day. At our present rate of consumption, oil, coal, gas, uranium, rare-earth metals, forests, nutrient-rich soils, clean water and many other critical resources will run out one day if sustainability is not fully implemented.
And I remind you…we ARE living on a remote island.