The original arrangements in each 76-year period became unworkable and unraveled toward its end. Eighteenth-century Americans rejected the colonial status quo and launched a revolution and established a constitutional republic.
Nineteenth-century Americans went to war over expansion of slavery. Early-20th-century Americans grappled with the collapse of the private-sector economy in the Depression of the 1930s.
We are seeing something like this again today. The welfare-state arrangements that once seemed solid are on the path to unsustainability.
Entitlement programs — Social Security, Medicare, Medicaid — are threatening to gobble up the whole government and much of the private sector as well.
Lifetime employment at one big company represented by one big union is a thing of the past. People who counted on corporate or public-sector pensions are seeing them default.
Looking back, we are as far away in time today from victory in World War II in 1945 as Americans at the time of the Dred Scott decision were from the First Inaugural.
We are as far away in time today from establishment of Social Security in 1935 as Americans then were from the launching of post–Civil War Reconstruction.
Nevertheless our current president and most politicians of his party seem determined to continue the current welfare-state arrangements — historian Walter Russell Mead calls this the blue-state model — into the indefinite future.
Some leaders of the other party are advancing ideas for adapting a system that worked reasonably well in an industrial age dominated by seemingly eternal big units into something that can prove workable in an information age that is experiencing continual change and upheaval wrought by innovations in the market economy.
The current 76-year period is nearing its end. What will come next?