My guess is that it depends on how strong and close the relationships, connections, and organizations are among the people who are there when the collapse happens. Also, it probably depends on how quickly or slowly the old way of life (hierarchy, government, etc) falls apart. I'd imagine another factor is the collective mindset of individuals - how they view life and death, how fearful or fearless they are, how much they've come to value their uniqueness and diversity, and so on.
For me, the primary question is how would I and how do I respond during times of unrest as well as in times when it seems to be business as usual. What am I willing to risk? How important is safety...or freedom? Can I imagine myself in another situation other than that in which I currently reside? How can I imagine my life now, despite what seems to be "reality"? What to do in the face of warlords, or the seeming absence of them when I am feeling comfortable?