One big idea out there is that what we need is Exit. We need to allow secession, for different people to go their own way. We obviously can't get along. Some people want homosexuals teaching sex education in kindergarten. Others want to put statues to Hitler and Genghis Khan. Others want the liberty to do drugs, own guns, preferably at the same time. Others want soda taxes enforced by a mercenary army. Many want sharia law.
That's what other countries are for! Give us borders. A patchwork, a polyhedron of independent countries free to develop their own culture. That's a fine idea. Autonomy is a fine thing. Surely better than having faceless bureaucrats ruling from thousands of miles away.
Well ok, let's say we all get secession. What happens then? Fortunately Europe is experimenting with the idea. Plenty of secessionist movements going on in Europe. Scotland is one of the most advanced. Soon Scotland may be able to become free, and the Scots can do their own thing. So what are the Scots up to?
They are basically running the mother of all censorship campaigns by arresting anyone who says anything non-PC on the internet. Hate crimes, you see. Even the Chinese Communist Party isn't this blatant.
It is often said that the secret of European dominance after the 16th century was that Europe was divided in many small states, which created a competitive pressure which resulted in, well, massive advances in shipbuilding, weaponry, science, and eventually the Industrial Revolution. I buy that. But you'll note that for all the political division of Europe there is such a thing as European culture. European countries had different governments different languages.Yet they dressed mostly the same, had similar economic systems, basically the same religion. The elite intermarried profusely, and intellectual life was international. Many linguists will tell you that European languages, for all their differences, are basically the same; vocabulary and other grammar patterns having diffused so much that automatic translation actually works! Try to run Google Translate to any slightly exotic language and it breaks down very fast.
Even if the Western elite were to go mad tomorrow and allow widespread secession; even if Europe and North America were tomorrow to divide in 500 sovereign countries; who says that the common culture would necessarily fracture? The Irish fought valiantly for decades to gain their freedom from the British, only to use their sovereignty to fill Dublin with African immigrants. The Scots are likely to use their newly gained sovereignty to pass a law giving 10 year jail sentences to those who oppose bringing 100k male Afghan immigrants per year. Which will make the British then bring 120k, to spite them. The same way Voltaire was a celebrity in both the Russian and Pussian courts, or Confucius roamed the Chinese heartland working for different lords, Sadiq Khan may end up as mayor of Berlin after he's finished with London.
I don't want to oversell this argument. Of course sovereignty does matter at some level. I'm glad that Slovakia or Hungary are sovereign and can refuse to open their borders to barbarians. If the EU could it would have forced the distribution of migrants across European territory. Still, sovereignty only gets you so far. The EU could plausibly engineer a regime change in some country in Eastern Europe in the middle term, and put some Harvard grad to implement EU policy.
The issue here is culture. Politics of course influences culture to some extent, but the arrow goes the other way around too. Any patchwork, no matter how sovereign, will result in the same insane liberal monoculture if trade dynamics stay the same, everybody learns English, the global elite all goes to American colleges, and everybody is discussing politics on Twitter. Sovereignty doesn't mean anything if the sovereign(s) doesn't want to use it. I've made that point about monarchy several times. It applies to republics all the same.