[rorroe53]

There are many practical problems to actually implementing this idea.

First, money. Some parts of the EU are way richer than others, with superior welfare systems. If every EU citizen is to be truly equal, then that would mean same standards of government services and welfare everywhere, which would be costly to the richer states. Of course, alternatively we could lower standards everywhere, but that's not good for people.

Then there's cultural, economic, geolocial differences in general, higher corruption in many members states of east/south... Plenty of things to consider. Leaders in some parts of the EU really won't understand the situation in other parts, which makes any kind of centralized government problematic. Perhaps a very decentralized model could work though, but then again that's not much different from what we have now.

Also, nationalism is hardly "an ancient mentality". Healthy nationalism, a common idea and identity is something pretty much all well-functioning countries have. United States of Europe would never work without a common European identity, and controlled outer borders. Cultural differences between different parts of the world are still way too large for anything like democratic one world government to work.