Many of the great ruins that grace the deserts and jungles of the earth are monuments to progress traps, the headstones of civilizations which fell victim to their own success. In the fates of such societies -- once mighty, complex and brilliant -- lie the most instructive lessons for our own.... Of course, our civilization's particulars differ from those of previous ones. But not as much as we like to think.... While the facts of each case differ, the patterns through time are alarmingly -- and encouragingly -- similar. We should be alarmed by the predictability of our mistakes but encouraged that this very fact makes them useful for understanding what we face today.
Indeed, weaponry and combat techniques threatened our existence once before, when the weapons were made of stone and warfare was directed primarily toward sources of meat. The trail of extinctions included much of the large prey. Without the discovery of intensive agriculture human beings might well have found the food chain collapsing beneath them.
On the other hand, a nuclear holocaust would be an altogether different beast. That order of catastrophe would certainly spring the trap and plunge us into a new dark age.