It's exciting to see the tangible success CES has made. And I think that repeatedly making the case for one big simple idea clearly, approval voting, is a powerful formula.
If "effective localism" existed, think approval voting would top the list for impactful reforms someone could take in their community, with zoning reform being a distant second for most communities.
At what point did you realize you regretted not continuing your political work? At that point what stopped you from re-engaging?
I have not explicitly searched out books to answer this question, but here is my understanding.
The best books have to be Asimov's Foundation trilogy.
The most relevant book to answer this question is Jared Diamond's Collapse: How Societies Choose to Fail or Succeed. It focuses on relatively isolated societies whose downfall was auto-catalyzed, mostly in the form of ecocide where a society annihilates its potential by over exploiting its natural resources. Most of the criticisms of the book appear to originate about how one case or another of collapse was in fact contaminated by outside influence.
Acemoglu and Robinson's Why Nations Fail: The Origins of Power, Prosperity, and Poverty and its sequel The Narrow Corridor: States, Societies, and the Fate of Liberty are good but not as relevent. Although they don't focus on civilizational collapse, many of their ideas seem relevant to thinking about the trajectory of civilizations. The books are sprinkled with a lot of interesting historical anecdotes about institutions and simple models about how they change, when they are destined for failure and how even if leading to ruin can stay bad for a long, long time.
It seems like there aren't many books written that take a comparative approach to studying dramatic regional declines in population / cities (my guess as a good proxy for collapse). Hope I'm wrong. There are certainly many popular cases written about local dark ages. Europe as depicted by Barbara Tuchman in A Distant Mirror: The Calamitous 14th Century is not strictly a collapsed civilization, but it's certainly tottering on the verge.
I would love to hear what other's think.