Studying the demise of historic civilisations
You know I lately think that, ok, we're mostly past the age of empires physically conquering one another, we're in the age of economic ebbs and flows of established countries.And in this kind of age, the thing that sinks a country is not aggression by others, but indifference and lethargy as a country "gets old"."Getting old" means the political desired and inertia of a rich, settled population get to dominate the goals and priorities of a nation, and it loses its drive to be scrappy, make sacrifices, and do the innovative things when one does when young and poor.  You have generations who want to extract the gains put in by past generations.  Or it costs too much to change people's behavior.That's what I think is happening to western Europe and the US.  Too many rich, old, soft people who now have settled and moneyed lives, and don't want to make the same sacrifices that the generation previously were forced to, by unfortunate circumstance.  Too happy with their 2nd homes and retirement plans.Unless you have a really conscious and socially adept mechanism to force a people to renew themselves, this sets in.    Sometimes, as sad as it is to imagine, I think you need a good war to refresh a country...