> there would no end of "EU is trampling national interests" and similar screaming

To just call this "screaming" is to completely dismiss a real and huge problem. The EU is the idea that countries should fuse into economic areas, but the countries are also individual still. Of course there's a lot of friction.

For example, because Greece was in the Euro, they couldn't inflate their currency to compensate for the fact that they gradually outsourced more and more work to Germany, until they had nothing left and hit a financial crisis because their government couldn't borrow more money. That's not mindless screaming.

Do you realize that your example actually counters your point? The Greece's example illustrates that a misbehaving minority shouldn't have an outsized influence on the majority, which is a correct thing to aim for, I completely agree with you on that. But the current EU arrangement actually allows minority entities to veto majority's initiatives and improvements, exactly because EU is not fully federated. 1 member country can screech and blackmail 26 other members for any arbitrary reason, and they all must comply with this minority's ultimatum. If EU was a federation, majority would simply outvote any obstructionists.

So you've described Greece as a bunch of scheming petulant children.

"Our plan to be inaccountable didn't work, so we'll try a different scheme instead".

And yes, it's a huge problem. That's why I called the situation unwinnable.