The complete inability of our society to deal with obvious consequences of our actions is what has doomed it. This society will not survive. The questions are only “How many people will it kill going down?” and “What will the next society look like in the ashes of a world left to us by this one?”
Whatever it looks like, it will be very different.
This all may sound pretty dire, but it probably isn't dire enough. That humans will learn from their mistakes after the collapse of civilization seems like a pretty meager hope, but even that may rest on the same optimism about progress and rationality that the rest of Welsh's post sets out to debunk.
It seems just as likely to me that the survivors are going to be just as prey to the same sociopathies as we are. They'll forget the lessons of history just like we do. They'll walk into the same progress traps. They'll kick cans down the road, and eventually it'll cost them.
There's no evolutionary reason to assume that we'll learn our lessons. Some species narrowly dodge extinction - and then they go extinct. Our mistakes will probably be too sudden and severe to exert the kind of selection pressures that would help us adapt. Consider global warming, for example: it is likely to destabilize civilization within a few generations. If the worst happens, it will completely consume us in a matter of centuries. And the first victims, of course, are going to be those whose ways of life contributed to the problem the least.
The Holocaust provides another instructive lesson on human adaptation, because it is a man-made catastrophe that much of world has taken deliberate and specific measures to avoid repeating. The resurgence of openly neo-Nazi parties and the persistence of genocidal aggression throughout the world shows how well that's going, but consider an even more basic point:
Among the Holocaust's survivors, it has always been a widely shared belief that memory is a crucial safeguard against its recurrence. That's why our culture was immediately flooded with memorials, memoirs, histories, analyses, dramatizations, and other artifacts: not just in mourning, but as a matter of documentation.
And that's why it's so alarming that today there remains no consensus over who the Nazis were or what it is about them that we are to avoid. The American right (and an increasingly large faction of Europeans) now insists that it was something about Hitler's handful of opportunistic socialist gestures that we should avoid - as opposed to, say, the gas chambers. This has obviously happened because powerful people have seen an advantage in transforming our collective memory into an ideological weapon against their enemies. And because of this, our society has become increasingly tolerant of precisely those dangers we set out to avoid.
So it is true that whatever civilization emerges from the rubble will in some ways look different. We may, for example, no longer have much fossil fuel or potable water at our disposal. But insofar as we find a way to survive, our worse instincts will probably survive along with us.