meritocrat

Is a federal state 'better' than a unitary state?

Take the US for example. What generally stops seperatists movements from forming if (for example) a particular state feels it warrants more autonomy?

I live in a unitary state (though since 1999 some areas of Britain have been granted autonomy in certain areas of governmental policy).

Kinross

For a nation with a large land mass i.e. US, a federal state is better. With distance comes different world views.

In the US you have the rural center and the more urban coasts. These two areas have a very different outlook on things and have different needs. A centralize government could not possibly address these needs efficiently.

As the land mass gets smaller there becomes less need for regionalization and eventually goes to the degenerate state of a unity state.

Misso

Like most political institutions, this is something that should fit a nationstate instead of be pushed onto it. France has a very strong unitary state, which works well for it, but Belgium had to make a federation out of itself a few years ago to prevent the country from falling apart.
Generally, when there are groups with fundamental differences living in one nationstate, a federation is needed to keep the nationstate together. It may also be desireable from a viewpoint of seperation of power: a unitary government could become too powerfull. This is also it's weakness: the state will, in a federal system, most likely not be as competent as it could be in a unitary system due to conflicts in the chain of command.