Sometimes secession from a despotic or failing state can be a matter of life or death. So it was for the former states of Yugoslavia in the early 1990s or the Kurds in Iraq and Syria today. So, too, for Georgia and Ukraine, among other former Soviet republics fighting to remain independent of Vladimir Putin’s new Russian empire. But for western Europeans today–living in a peaceful post-history paradise where the biggest issue most people confront is where to spend their month-long vacation–there are no such existential issues at stake. Yet secession has become a contemporary fad, more a matter of sentiment, ideology, and vanity than life or death.

For the outsider it can be hard to figure out why many in Catalonia want to leave Spain, why many in Flanders want to leave Belgium, why many in northern Italy want to leave the rest of Italy, why many (OK, perhaps only some) in Bavaria want to leave Germany, and why many in Scotland want to leave the United Kingdom–something that they may accomplish in a referendum this Thursday.

Granted, there are differences of culture and history and language that separate each of these regions from the rest of their countries–but these may well be less than the differences that separate New Mexico from Minnesota. If Americans can live together in one big country, aside from that minor trouble from 1861 to 1865, why can’t Europeans? Especially now that national boundaries mean less than ever in the context of the European Union, it is hard to see the pressing need for all of these regions to break off into separate countries.

Yet if the Scots vote for independence this week, it will give a powerful impetus to these other wannabe states. Where will it end? Europe could be undoing the work of 19th century statebuilders such as Bismarck and Mazzini, or farther back the various kings of England and France who subjugated once-independent lands from Wales to Brittany. We could be seeing a return to a continent of hundreds of tiny duchies, kingdoms, and states loosely united under today’s version of the Holy Roman Empire–the European Union.

This may satisfy the esoteric whims of tribalists whose identity is wrapped up in Catalonian or Scottish ethnic identity but it is hard to see why it is good for the continent as a whole–or for the world. Already the EU is an unwieldy conglomeration that cannot exercise power on the world stage commensurate with its gross GDP, which is roughly the same as that of the U.S., or its total population, which is even greater than ours. How much worse would the problem become if the EU has not 28 member states, as today, but 40 or 50–if, in short, it starts to resemble a European version of the United Nations. This may seem far-fetched, but it’s hard to know where the trend toward tribalism will end.

The most immediate issue, of course, is the fate of Scotland. It would not be a disaster for anyone involved for Scotland to become a separate country. Scotland would be a prosperous liberal democracy just like the United Kingdom. The UK (current population 64 million) would remain a great power even with the loss of 5.3 million Scots. Britons and everywhere else would still be free to visit the Highlands and drink as much single-malt as they can afford. But there would be inevitable transition costs that could run into the billions of pounds. Britain, in particular, faces the loss of its only port for its nuclear-armed submarines.

One could see the costs of separation as worth bearing if the Scots were oppressed by the English. But they’re not. The Scots actually have not only their own parliament to handle most internal affairs but also a substantial contingent of MPs who sit in Westminster where they can vote on matters affecting all of the United Kingdom. This is hardly “taxation without representation.” It’s more like welfare subsidies with over-representation.

There is, in fact, no compelling reason for the Scots to go their own way, any more than there is for Flemings, Catalonians, northern Italians, Bavarians, or others. All of the activists who devote energy to these causes would be better advised to create Internet startups that will deal with the real problem of Europe–which is slow economic growth and anemic job creation. All of these sectarians need to grow up and realize that they need to be able to get along with people who are marginally different from them–and in the context of global politics the differences between Scots and English today truly are marginal.