The map of Europe has started changing again. I had expected Scotland to be the first European border change of the 2010s, but Crimea beat us to it.
Scotland will also not be the first former country to vote Yes to independence in a referendum -- Veneto got there first (although it was an unofficial referendum with no legal force).
As I've discussed before, we might have reached one of those points in history when the equilibrium is punctuated and a whole wave of new countries will appear.
Of course the size of the wave might vary a lot. If Scotland votes for independence, Wales and/or Northern Ireland might follow. An independent Catalonia will probably lead to other nations leaving Spain, at least Euskadi (Basque Country) and Galicia. The recreation of La Serenissima (the Republic of Venice) will most likely lead to an exodus of new countries from Italy, such as Lombardy and Sardinia. And although I'm not aware of any significant independence movement in Baden-Württemberg, that could change quickly if Bavaria left Germany.
Unfortunately, I'm not aware of any really good list of independence movements. There's one on Wikipedia, but it includes "movements" that are really just the dreams of a few individuals, which makes it hard to work out the number of likely new countries.
While we're on the topic of independence movements within the EU, there were some rather interesting ideas in an article by Graham Avery entitled Independentism and the European Union:
The EU has no preference for bigger rather than smaller states, or vice versa; one of its principles is to ‘respect the equality of member states’. However, in its system of decision-making the EU does have an inbuilt bias in favour of smaller states. For seats in the European Parliament and votes in the Council by qualified majority, smaller states are over-represented in terms of population; they also have relatively more voting power than bigger ones. This ‘degressive proportionality’ is designed to give smaller states the reassurance that they will not be dominated by the bigger states.
These aspects of the EU’s structure and functioning evidently create an environment in which independentism can be more credible.
In considering how to deal with independentism today, member states of the European Union are fully entitled to insist that the principles of democracy and constitutionalism should be respected. They should also accept that – in relation to the EU – independentists are entitled to follow the logic of the structure that member states themselves have devised.
To be fair, it's not just because of the EU. The existence of a whole network of international organisations (the UN, NATO, the EU, the IMF, the International Court of Justice, the European Court of Human Rights and all that) creates a situation where countries have rights and obligations, and the application of international law means all countries are equal. This arguably favours small countries over large ones because the former are more homogenous and quicker on their feet, but vulnerable to being bullied by big countries (as Georgia and Ukraine have recently discovered).
It was tough being a small independent country three hundred years ago (and it still can be outwith NATO and the EU), but these days it's really not very obvious any more how Scotland benefits from being part of the UK.