I read a book one time that was based on the theory that every leader has a constituency that must be satisfied in order to remain in power. You could almost compare this to feeding young calves out in the pasture with entrance bars that prevent the rest of the herd from eating while the favored calves can have access.
In a democracy, constituencies have to be large enough to get elected and then must be rewarded, but enough scraps have to be tossed to the opposition to keep them sullen but not mutinous. This is why in Western countries change comes slowly rather than radically.
In Totalitarian regimes such as Russia, China, Iran and Venezuela you have to determine what is the group that supports the leader and how are they rewarded. In Venezuela the army keeps Madura in power and gets the good food, monthly pay and decent places to live. The same in Iran except the top clerical leaders along with their shock troops, the Revolutionary Guards, get all the goodies.
