I have had people misunderstand this so I want to be plain, I am not talking about being a community leader like some sort post apocalyptic novel. I mean you have to join with people who will give a damn if you live or die.
Family, church, neighborhood, club, does not matter.
I spent a lot of years overseas and one thing that held true in every country was expats stuck together. You needed something and someone would see you got it. We were strangers in hostile territory. No one was coming to rescue us if it went sideways. So we looked out for each other. We were not all angels but were a community.
Weave your own safety net or drown in the coming storm.
I believe your last statement is one of the most meaningful suggestion, and deserved special emphasis.
Build up your community .. now !
Anticipate problems before they stare you in the face, and you have to emotionally react!
If you expect regional violence, join a gun club and develop friendships now, and use their skills and knowledge, and prepare for barter.
If you expect food shortage, join a local fresh food club or develop a relationship with local farmers, or gardeners in your area; know your grocer who can adivse of incoming shipments.
If you expect taxation issues, develop a relationship with several CPAs or accountants in your area; use their knowledge as to proposed tax changes.
In the words of a past political agent (paraphrased): " If one of us swings, we all swing, together "