No communist or fascist state has survived longer than 100 years.
Democracies and Republics are what tend to fail. Don't know of any historically besides Switzerland which have gone 200 years without becoming a socialist mob rule statem. The mob gets full franchise rights eventually... the productive people get robbed blind to pay the looters and eventually when Atlas Shrugs a dictator comes to power.
Really? Ever heard of the feudal system?
I believe that the US is now a quasi-fascist state. The only reason that it survives in the US is that the citizens are armed, and that right is supposedly protected by the Constitution.
As more and more laws regulating and controlling firearms ( and other aspects of our everyday existence) appear, the US will move ever closer to the classical definition of Fascism. At some point, this movement will spill over into open conflict.