Our Global Crisis: "We'll Never Run Out!"

Modern society has reached a critical juncture in its existence. Like past civilizations ours has reached a point where its future is far from certain, with its decline, or even collapse, being distinct possibilities.
The Incas, the Mayans, the Romans, the Rapanui, and many others, had seemingly successful societies, yet collapsed when faced with challenges that threatened their continued existence.
Are we to suffer the same fate? What could possibly cause our downfall?
Climate change and envi...