A fantastic overview of the drooling rabid daft school of Marxism called Multiculturalism.
Human beings do not drive biology. They are driven by biology.
When civilizations approach their 200 year limit, there is nothing that can stop the inhabitants from recklessly throwing themselves headlong into suicidal enterprises of one flavour or another. Nothing. Give me death or nought liberty, they scream. They thirst for death, they pursue it by a thousand means and seek to be destroyed by whatever opportunity presents itself. Everything they do is engineered to wreck themselves and everything their culture has managed to construct. This ancient cyclic commandment is as powerful as the sex drive and more persistent. The lemmings will not be frustrated by fences or roads - they drive forward towards the cliffs with all the strength they have left in their bodies. Biology commands them to annihilate themselves. Whether they do it by abortion or narcotics or fallout does not matter. Biology commands them.
How odd the nuclear shelterist must seem to such people, traveling in the exact opposite direction, accompanied by no consensus, the last word in unfashionable! Where is their peer group? Didn't they get the memo from Mother Nature? We are all to rush forward to the cliffs! It's trendy, it's hip, it's somehow inexplicably sexy ... what on earth is that fool doing building shelter, storing up food and preparing himself like he wants to live instead of die! How unbelievably strange it must be for thousands of lemmings to pass by a single lonely rodent digging a burrow with a shovel and saving up nuts for the winter! There is no longer a need to ever fear the winter again, they scream as they pass in their teeming millions. We are all to rush forward to the cliffs! You don't want to be left behind, do you?!?
The big difference in the modern era is nuclear weapons. Thousands of civilizations that we know of have willfully exterminated themselves through their own efforts. Ours is the first (that we know about) that has the nuclear option as a tool to achieve their own genocidal desires. This is why Vault-Co predicts that this extinction cycle is not just going to consist of one geographic area or one narrow regional failure. It's not just the Sumerians, the Abyssinians, the Romans, the Carthaginians, the Russians, the Americans. This cycle is going to be worldwide.