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Some academics have studied this issue. The very popular theory today concerning it is the Strauss-Howe Generational Theory or the Four Turnings, which I believe only applies to US history. They created this theory to try to help some of the problems which will occur, since we can expect them.
Strauss and Howe lay the groundwork for the theory in their 1991 book Generations, which retells the history of America as a series of generational biographies going back to 1584.1 In their 1997 book The Fourth Turning, the authors expand the theory to focus on a fourfold cycle of generational types and recurring mood eras in American history.[2]
These are the theorist who believe that the Millennial Generation, defined as those that graduated high school starting in 2000, are the historical analogue to the WWII's Greatest Generation. They are the result of the "Fourth Turning."
today's teens and young adults are recasting the image of youth from downbeat and alienated to upbeat and engaged. They write that Millennials are held to higher standards than adults apply to themselves; they're a lot less violent, vulgar, and sexually charged than the teen culture older people are producing for them. Over the next decade, they will transform what it means to be young.
Here are the Turnings:
First Turning is a High (Silent Generation). This is a post-Crisis era when institutions are strong and individualism is weak. Society is confident about where it wants to go collectively, though those outside the majoritarian center often feel stifled by the conformity.
the Second Turning is an Awakening (Baby Boomers). This is an era when institutions are attacked in the name of personal and spiritual autonomy. Just when society is reaching its high tide of public progress, people suddenly tire of social discipline and want to recapture a sense of personal authenticity. Young activists look back at the previous High as an era of cultural and spiritual poverty
the Third Turning is an Unraveling (Gen X). The mood of this era is in many ways the opposite of a High: Institutions are weak and distrusted, while individualism is strong and flourishing. Highs come after Crises, when society wants to coalesce and build. Unravelings come after Awakenings, when society wants to atomize and enjoy.[24]
the Fourth Turning is a Crisis. This is an era in which institutional life is destroyed and rebuilt in response to a perceived threat to the nationβs survival. Civic authority revives, cultural expression redirects towards community purpose, and people begin to locate themselves as members of a larger group
(Apologies for so much cut and paste) There are many other theorists that have looked at the reasons for the cycles of peace and war in societies, as well, but I suggest starting here.