It is noteworthy of the 20 crises on this list, 15 of them are in Africa.
Perhaps this is no surprise, since the continent has been the object of untrammelled greed since the earliest days of its exploration by Europeans, and featured the worst excesses of colonialism.
This was followed, in turn, by the worst excesses of corrupted liberation ideology, blended with ancient tribal hatreds, and manipulated international politics to make a hellish political cocktail.