My favourites for the most likely are 1) Nuclear Armageddon and 2) Overpopulation. With the former a very real possibility.
Having more than a passing knowledge of the Russian psyche suspect that as we push them harder with sanctions over Ukraine, the more they will adapt a siege mentality and become more belligerent. As their economy is almost entirely based on the price of their exported oil, the present situation isn't helping. Did my bit fifty years ago in the Cold War. Could be interesting a second time around.
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Rev Mother Bene Gesserit
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