I'm not sure what you mean by "work". The USSR didn't "work" very well, either, in that it was an economic disaster scene. But it was effective at maintaining power. People who desire power don't necessarily care if they're acting in the best interests of the people they wield power over.
The fact remains, the governments of Europe have been very happy to turn over large portions of their sovereignty to the EU. One of the most important cornerstones of sovereignty is monetary policy, and they pretty much surrendered that without a fight. That doesn't bode well for their willingness to fight for their independence in the future.
The wild card there is the EUro. In this you are quite right, you cannot have a currency without political institutions. They may have to ditch it.
That would certainly be nice, but I don't see the same people who agreed to the Euro, all of the sudden turning around and ditching it, unless they feel very large amounts of heat from their constituents. There are rumblings in that direction, but Euroskeptics have a big work load cut out for them. And it's a lot easier on an economy to create a currency than to get rid of it.
I should not say that for the real impetus behind all of this was not commerce, of course, but this bizarre simulation of the USA as vehicle for power from the Eurocrats.
The impetus behind it was power, plain and simple. Back when it was just a "free trade zone", its architects knew what they were creating. They knew quite well. This isn't just some post-Cold War, try-to-keep-up-with-the-U.S. fad.
As to the Euro, I did not mean that that would happen overnight but in time. In fact I do not see how it cannot happen. A currency without a country? will not work in the end. The "Club Med" credit problems may in fact tip it over sooner rather than later.