The USA has peaks of violence in 50 year cycles

[Raze]

https://archive.ph/IilTf#selection-1505.0-1512.0

Quote

 In 2012, Turchin published an analysis of political violence in the United States, again starting with a database. He classified 1,590 incidents—riots, lynchings, any political event that killed at least one person—from 1780 to 2010. Some periods were placid and others bloody, with peaks of brutality in 1870, 1920, and 1970, a 50-year cycle. 

https://peterturchin.com/PDF/Turchin_JPR2012.pdf

[Bojan V]

This is all very interesting but it  doesn't consider the american imperialism, killing people in other countries. This happens more or less constantly.