Supposedly Steve Bannon is influenced by a book called The Fourth Turning that hypothesizes a cyclical view of history. Wikipedia refers to its primary author, Neil Howe, as an “amateur historian”, although he actually does have a history degree from Yale. Here is Howe talking about his own book in the Washington Post.

Along this cycle, we can identify four “turnings” that each last about 20 years — the length of a generation. Think of these as recurring seasons, starting with spring and ending with winter. In every turning, a new generation is born and each older generation ages into its next phase of life.

The cycle begins with the First Turning, a “High” which comes after a crisis era. In a High, institutions are strong and individualism is weak. Society is confident about where it wants to go collectively, even if many feel stifled by the prevailing conformity. Many Americans alive today can recall the post-World War II American High (historian William O’Neill’s term), coinciding with the Truman, Eisenhower and Kennedy presidencies. Earlier examples are the post-Civil War Victorian High of industrial growth and stable families, and the post-Constitution High of Democratic Republicanism and Era of Good Feelings…

Finally, the Fourth Turning is a “Crisis” period. This is when our institutional life is reconstructed from the ground up, always in response to a perceived threat to the nation’s very survival. If history does not produce such an urgent threat, Fourth Turning leaders will invariably find one — and may even fabricate one — to mobilize collective action. Civic authority revives, and people and groups begin to pitch in as participants in a larger community. As these Promethean bursts of civic effort reach their resolution, Fourth Turnings refresh and redefine our national identity. The years 1945, 1865 and 1794 all capped eras constituting new “founding moments” in American history.

Supposedly, Bannon’s theory is that the 2008 financial crisis is the latest “fourth turning”. There are lots of critical takedowns of these ideas online, calling them “pop history” or “pseudoscience”. For example, here is the original New York Times review of the book in 1997, and here are recent articles in Huffington Post, Business Insider, and The Nation.