USA, Beware 2020
Both Nature and New Scientist recently covered the work of Peter Turchin, who suggests, based on prior trends, that the US is in for a new period of political instability peaking around 2020. He finds that historically US instability has peaked about every fifty years:

He also found this 50 years cycle in Roman and French history, but not in Chinese history. This evidence seems sufficient to mildly raise my expectation of instability at that time, relative to what I would have otherwise thought. Turchin also sees a 150 year cycle in six (de-trended) parameters that suggest instability:

This suggests a US peak in the decades surrounding 2040. Other civilizations have had such long waves, but with widely varying periods. This also mildly raises my expectation of instability in that period.
Even so, the strongest trend we see is a long term worldwide decline in such things. So my strongest expectation is for a continued long term decline in instability. But yes, let’s watch out for the US in 2020.