History's Not Cyclic, But Parts Of It Rhyme

 1914 - 1918, World War One
 2001 - tfn, Global War On Terror

 1917 - 1920, Influenza Pandemic
 2019 -2021(?), Coronavirus Pandemic

 1920 - 1925, Radio Broadcasting, a consumer-friendly application of a geeky technology, becomes wildly popular
 1994 - 2005  The World Wide Web, a consumer-friendly application of a geeky technology, becomes wildly popular
 2004 - tfn, social media (Facebook and others), a consumer-friendly application of a geeky technology, becomes wildly popular

 1919 - 1929, increasing -- and increasingly causal -- investment in the stock market expands from the wealthy to the middle class, ending in a crash.
2000 - ????, increasing -- and increasingly causal -- investment in the stock market expands from the wealthy to the middle class, ending in ????

 1929 - 1939, global Great Depression
 202? - ????, ??

 1928 - 1939, rise of fascism in Europe

 1939 - 1945, World War Two

     Buckle up, it could get bumpy.