Meeehhhhh. Ok, I'm going to slightly dissent and note that we're on our way to creating a second rise of fascism at the moment in much of the Western world. That is, even though our economies and societies are easily capable of keeping everyone alive, on a collective level we're currently choosing to force large numbers of people into Survival Mode, which frankly is an even greater mindkiller than blue-green politics. Get large numbers of people into Survival Mode and they start making really stupid decisions, like marching down the streets of the capital yelling "Jews out!" and demanding a strengthening of the military... in an EU member-state with barely any Jews in it.
Did I just refer to France or Greece? Both.
On the other hand, I don't think population trends really allow for militarization and total war anymore, and the rise of Asia means that someone's around to smack Europe and America when they get too stupid.
So we could be looking at some waves of terrorist violence if public policy remains terminally obstinate about forcing people into their brain's mind-killed survival mode no matter the material facts, but probably not another Great War.
I'm taking about a much worse scenario.
Death, long lives, uploading
Mark Rosenfelder (aka zompist, of language construction kit fame) writes about the advantages and drawbacks of mortality and its alternatives, in fiction and real life. Rosenfelder, as an author, clearly takes Fun Theory very seriously. After discussing the mental and physical decline that age usually entail, he assumes that the most difficult to surmount of these problems will be the loss of mental flexibility and tolerance of novelty. He then uses this obstacle to offer interesting fun-theoretic arguments against uploading and cryonics:
And how he addressed the issue in his own far-future conworld: