Strauss & Howe do a really good job of detailing the overlapping generational theory and each generation’s corresponding archetype in The Fourth Turning. 20-22 years is about the average length of each generational period with every saeculum spanning approximately 80-90 years or roughly the length of a human lifespan.
History is seasonal and winter is coming. The very survival of the nation will feel at stake. Sometime before the year 2025, America will pass through a great gate in history, commensurate with the American Revolution, Civil War, and the twin emergencies of the Great Depression in World War II. The risk of catastrophe will be high. The nation could erupt into insurrection or civil violence, crack up geographically or succumb to authoritarian rule. If there is a war, it is likely to be one of maximum risk and effort — in other words, a total war. Every Fourth Turning has registered an upward ratchet in the technology of destruction, and in mankind’s willingness to use it.
–(The Fourth Turning, Strauss & Howe, 1997)
