Unceasing warfare gives rise to its own social conditions which have been similar in all epochs. People enter a permanent state of alertness to ward off attacks. You see the absolute rule of the autocrat. All new things become dangerous frontier districts-new planets, new economic areas to exploit, new ideas or new devices, visitors-everything suspect. Feudalism takes firm hold, sometimes disguised as a politbureau or similar structure, but always present. Hereditary succession follows the lines of power. The blood of the powerful dominates. The vice regents of heaven or their equivalent apportion the wealth. And they know they must control inheritance or slowly let the power melt away. Now, do you understand Leto's Peace?
Attributed to: Leto Atreides II
From Chapter 18 of God Emperor of Dune by Herbert, Frank