I know I posted this yesterday on this thread, but I accidentally deleted it, so I'm going to repost it.
There's actually an interesting political cycle theory related to this.
This is how it goes:
Hoover-Carter: Both of these politically moderate presidents are considered failures, and because of them an era of liberalism/conservatism begins.
FDR-Reagan: Both presidents considered heroes of the left/right, both ushered an era of liberalism/conservatism, and also "defeated" foreign enemies of the far-right (Nazi Germany), and the far-left (Soviet Union).
Truman-Bush 41: Both vice-presidents of the previous administration, and are one-termers who had really bad approval ratings by the time reelection came along, and failed to live up to the previous president. Both presidents also ended tensions with past enemies (Truman: Nazi Germany/ Bush 41: Soviet Union), and created new tensions (Truman: the beginning of the Cold War, Bush 41: beginning of tensions with the Middle-East with the Gulf War).
Eisenhower-Clinton: Both were moderate heroes, who ushered a decade of peace and prosperity.
JFK/LBJ-Bush/Cheney: Both Bush and JFK were members of a political dynasty, whose election to the presidency was against the vice-president of the former administration. The two vice-presidents (Nixon/Gore) were extremely uncharismatic, and lost the election by a razor-thin margin, despite the last president being very popular. Both JFK/LBJ and Bush/Cheney increased tensions severely with foreign enemies (Soviet Union/Middle-East), and ushers a decade of war (Vietnam/Iraq and Afghanistan).
Nixon-Obama: See this thread: https://uselectionatlas.org/FORUM/index.php?topic=168317.0
So following this cyclical theory, a moderate Republican should win narrowly in 2016, and lose in 2020 to a far-left Democrat who ushers an era of liberal dominance.
It's all so neat; if only it went backwards. But I don't see the parallel between Coolidge and Nixon (or Obama for that matter). I think the better way to think about the parallelism in those two epochs is to study the events which shaped them, rather than the outcomes. From the way you've set the "cycles" up, they have a common origin in a financial crisis of catastrophic proportions which combined the incumbent presidents to 1 term and naturally led to the election of candidates who offered big shiny new solutions which became the defining dogma of their respective factions for the next several decades.In 1980, there were a lot of economic problems, but far from "financial catastrophic proportions". I think it was a combination of things that made Jimmy Carter sort of the democratic Herbert Hoover.
About the democrats possibly dominating in this presidential cycle: It could more demographic than ideological. Who knows, though.
Domination cycles:
1800-1824
1828-1856
1860-1892
1896-1928
1932-1964
1968-2004
2008-
