Europe does not share a language in common, a culture in common, not even a currency in common. The "federal government" idea would be rejected by many out of hand. The history of bitter wars between European countries has not simply been forgotten and many would feel it encroaches on their sovereignty.
Just look at the reaction to mild proposals for an EU armed force as an example, or the many "Euroskeptic" politicians going around.
I think you underestimate what it takes to form a strong federal government.
* Responsibility to implement treaties remains with the individual members. * No ability to tax or set fiscal policy.
The advantage of a single set of laws is obvious. For starters I wouldn't be spending my Sunday reading a 500 page document on minor items describing how Denmark's implementation of an EU treaty differs from the treaty's wording. (Although it would cost the jobs of the people who produce such documents, and as such would fly in the face of the one central pillar of paneuropean identity).
The ability to tax and set fiscal policy is needed to offset the imbalance created by the single currency. Another lengthy topic, but basically the assumption that every EU member should "export" is simply impossible. A normal currency system would correct a trade imbalance automatically. The euro systematically undervalues the cost of German output buy forcing their European neighbors to transact in the same currency.
And then you have mafias, bankers, tax havens, uneven social nets, and a raft of other social problems that can only effectively be dealt with by a central government. The irony should not be lost that the American government has had better success battling the Italian mafia than the Italians have.
Minorities don't care well under powerful central government. Unless that government is a minority dictator tha terrorizes the majority.
Would you enjoy being europe's version of an Uighur in China?
> And then you have mafias, bankers, tax havens, uneven social nets, and a raft of other social problems that can only effectively be dealt with by a central government
US has all these problems even worse than Europe except maybe the mafia next the mafia took over the government directly.
With the turn the democratically elected Hungarian and Polish governments have taken the past few years, I sure hope there won't be a powerful federal EU government any time soon.
Germany tried that twice but the Americans stopped it. Either because the US didn't want that particular genocide or because they didn't want a unified Europe under european control.