Secession is not just a means of creating new countries, but can become a central element in governance in general. The general principle is that at any level of government, lower-level governments or individual residents may secede in part or in whole.
This is from a paper by our own Dr. Foldvary. Do read the whole thing. One thing I get tired of dealing with is the “confederate!” slur that is inevitably hurled my way when I bring up secession as a legitimate political function. In other parts of the world, secession is just as hotly debated (if it is not a forbidden subject to talk about).
I think there is a good case to be made that secession would get better reception once a larger (and lighter) federal or confederal system is place, and then allowing for mechanism of decentralization to happen. This way the polities under each system are still bound to each other economically or in some small political way, and would thus likely keep the threat of violence to a minimum.
Dr. Foldvary’s fascinating paper touches on this, too. Just read it!