I've been following the Turkey diaries as well, and I can't recall that anyone has advocated membership as a solution to a "hypothetical clash of civilizations".

But be that as it may:

I agree that neither Turkey nor the EU are ready for each other - at present. But if Turkey keeps making progress, then membership in 15 to 20 years looks more feasible. It's a matter of political will on the part of the Turks.

Likewise, the EU as presently constituted is in no position to keep adding member states and continue to function effectively. But there is no reason it cannot become so - it's all a matter of political will on the part of the Europeans.

Your quote from Clair Berlinski respecting the nation state:

The nation includes those who share a particular historical, linguistic and cultural heritage.

overlooks, IMO, the arbitrary nature of the "nation". At what point do people decide they have more sameness than differences? In the case of France, when did people stop thinking of themselves as Acquitainians and Burgundians (both groups with greatly different "linguistic heritages", IIRC) and consider themselves French. More recently, the idea of the "German nation" practically didn't exist before the Napoleonic Wars, and the invention of the Italian nation under the King of Savoy came even later.

Consequently, Berlinski's assertion:

Unsurprisingly, it is difficult to cobble nation-states together into a grand transnational entity.

is not entirely accurate historically: that is just what the "Germans" and the "Italians" chose to do.

BTW, I find Berlinski's explanation for the French rejection of the EU constitutional treaties disingenuous:

All of European history - all of world history - argues against a federation with no force to back it up and no way to impose its will on member states.

So that is why they voted against a measure that would strengthen the central authority?

Turkey can qualify for Europe. And Europe can become an effective political entity. Why not?

You speak of ...the Europe i dream, the identity i want, affinity i need. Perhaps you could describe these?

The fact is that what we're experiencing right now is a top-down disaster. -Paul Krugman