Part of the reason the current moment--global conflict, rise of populism, resentment, etc--has been so surprising to most in the policy space is that they were trained in the standard economic thinking of the time, which emphasized material comfort above all else.
The emphasis on material comfort gave rise to the worldview that if we were all just better connected, if prosperity could be shared through fair trade and economic relationships, then conflicts would melt away and we would approach "the end of history". Friedman's famous "McDonald's" theory is a good example of that--put a McDonald's in every country and we will have no wars and strife.
But this ignores basic human psychology: moral values, need for status, mimetic desires to dominate, need for meaning through sacrifice/religion are all integral to human motivation. These motivations operate all the time, but become even more extreme when material comforts *are* met. This is when people start looking for status and meaning on dimensions that seem self-destructive, fighting "metaphorical wars". You can see this in the divergence of values over time: as economies have become increasingly globalized and overall prosperity has increased, human values have *diverged* (see paper in reply).
These motivations are also why any "utopia" will always be doomed to fail.
Unlike many on here who critique economics, things like status, identity, mimetic forces are not outside the standard economics toolkit. There have been plenty of important papers written on status-seeking, culture, norms, and mimetic forces. But most of this work is either relatively recent or was on the periphery of economic thinking that permeated policy circles.
Fukuyama was so prescient. In a society with strong rights and material comfort, but light on demanding shared purposes and some degree of sacrifice, thymotic energies go searching. Some quiet into bourgeois hedonism; other will seek “metaphorical wars” and eventually real ones.