I was sitting at the library reading The Story of B by Daniel Quinn, a second reading for me on that particular book. There is one lecture given by the character B, where he goes through the doubling of population through the ages. He details how the problems facing complex societies, from the instituting of kings and rulers as war chiefs, to crime, corruption, plague, famine, and the like, get worse as populations grow more crowded. Reading the section, now I forget the exact years, but it was something like 1500-1700, as he's talking about how as the population has doubled yet again the issues have gotten worse, he mentions in passing something about the New World.
It occurred to me that the New World was sort of a pressure valve for the Old World, Europe especially. Just as Europe was starting to really rub up against its geographical limits, and therefore whatever limits the land's carrying capacity entails, just as any possible agricultural land had been put to the plow, just as the rivers and nearby seas were about fished out, just as the socio-political pressures were building to really dangerous levels, an avenue of release was found.
Now Europe could continue expansion without the dangerous conflagrations of peasant revolts and uprisings, or at least with somewhat less of them. They could grab the riches of the new lands, the timber, furs, gold, and silver, and thus have the material with which to continue the project of civilization. They could reap the fish, the new crop-foods, could colonize and farm the new lands, and so feed their hungry masses. They could shunt off the agitating lower classes and religious sects to the New World, far from the political power, thus weakening their complaints further. They could ship criminals off, could sell the street urchins, beggars, and poor into indentured servitude, a fate often worse than actual slavery.
Just as Europe was reaching a crisis point, it almost seems, it found a backdoor for a brief respite. Much like the development of the North Sea Oil Field put off Peak Oil for a couple decades. Because this backdoor into the Americas was only a prolonging of things. Now the Americas are in many ways filled up and used up. Most agricultural land is in service (there are exceptions, like land the government pays to keep fallow, for price controls, for example). Most of the old forests are gone, most of the major gold deposits have been mined. We were again saved by the Green Revolution, which increased crop yields, but in a way it was a Trojan Horse: we grew the population while destroying the soil's ability to produce, and created superweeds and superpests, each with a growing resistance to our pesticides. Sometimes the soil just washed or blew clean away.
We're living on the dregs, just as Europe was around the time the New World was discovered. They were certainly growing close, at least. And so are we. We're tearing down the Amazon to grow beef and soy, but each acre only lasts in this way for a few years, before it is an exhausted wasteland. We are tearing apart Alberta for the last dregs of any sort of petroleum, like a junkie selling off the furniture and appliances for just a little more smack. We've pushed things longer with our technology, but that only means we'll have even less left when all is said and done than otherwise might have been.
The collapse that is 4 centuries in the making is looming again, and this time there's no escape.