Twenty years is an arbitrary time period, but historically it’s about the length of a human generation. The world changes radically in each generation, but the dates can vary. The last era began in 1991 and ended in 2008. Yet even now there are many who are waiting for the world of 1991 to return. More important, only now is the full power of what started in 2008 being felt. – George Friedman
The Geopolitics of the American President