The global balance would be substantially upset should one of the West’s key unions, and its second-biggest defense power, split up. The United Kingdom has always punched above its weight diplomatically and militarily. A breakup would have a serious effect on its role in the world — all the more so because Britain’s nuclear-deterrent base is in Scotland, and those advocating separation have pledged to expel it. With the United States and other countries viewing a possible British withdrawal from the European Union as negative, how much more disturbing would they find a breakup of the country itself?

The ripple effects would not be limited to the United Kingdom. Other separatist movements in Europe are watching the Scottish debate with undisguised interest. In Spain, more than a million Catalans have turned out in the streets calling for independence. In the Basque Country, separatist violence has waned, but the desire for a separate state remains. In Belgium, whose unity hangs on a thread, Flemish nationalists have made it clear that if Scotland has a free pass to the European Union and NATO, they would be next in line. There could be more breakaways to come.

The re-Balkanization of Europe should give many pause. In a fragile, unstable world where problems and solutions are going global, going local would benefit no one. Separatism offers little by way of comfort to worried populations. It promises more strife and dissension.