> Which 150 year period in US history are you comparing to which 30 year period in EU history?
The destruction of the states as meaningful sovereign entities and the rise of the central government, which accelerated in the late 1860s (prior to which most Americans would have considered themselves citizens of their states more than of America), got worse in the teens, got worse in the 30s and 40s, and has gotten progressively worse every decade since.
The difference is that the United States of America were a deliberate, intentional, open attempt to form a federal government, while the European Union was a slow-motion, back-door, sneaky attempt to form a centralised continental state.
The U.S. Constitution very explicitly limits the power of the central government: it restricts the government it establishes to very little more than what you mention (a navy, international treaties and interstate commerce). The proposed, rejected and then adopted anyway European Constitution, OTOH, rejected ironclad separation of powers in favour of fuzzy, undecidable things like the 'principle of subsidiarity,' which is of course in the eye of the beholder. What makes this particularly crazy is that America was a far more culturally homogeneous place in 1788 than Europe is in 2016: they should have taken things extremely slowly, imposing only the absolute bare minimum required and then stopping for decades before increasing centralisation.
Rather than learn from and avoid repeating America's death of federalism, the EU decided to just jump right in and annihilate its member states as meaningful entities.
Like I said, I think that a United States of Europe is inevitable. Heck, I think that a more-centralised America was also inevitable and in many respects desirable. But there's no need to accelerate the process. Take it slowly, take it soberly and take it judiciously.