History repeats itself?

I was away for 2 days and am just catching up on all the science reading today . . . hence a bunch of posts about cool articles. This article is particularly awesome. The scientists use "cliodynamics" or scientific methods to illuminate the past (and predict future events). They found that the USA has 50 cycles of violence. The motivating issues vary, but the violent political upheaval is surprisingly regular. The next one is expected to peak in 2020. THey also found that "empires" have cycles that extends over 2-3 centuries, which fits the patterns of instability that occurred across Europe and Asai from the fifth century BC onwards. Last year's Egyptian uprising fits right in with this.

Check out the article at Nature:

http://www.nature.com/news/human-cycles-history-as-science-1.11078