As you know, i've already pointed out elsewhere in another context that Europe (western Europe, to be sure) was able to develop economically behind an American military shield. I don't think that calls for stupid remarks about them being ingrates, or cowards. We had our own reasons for being there, and to a large extent, imposed on our hosts (although largely, there was the single host of Germany--Belgium had a great net benefit from providing NATO headquarters without actually providing facilities for large numbers of troops). The French threw us out because of national conceit (a wonderful example of political manipulation and self-interest on the part of Charles De Gaulle), but equally because they didn't need or want us there, and were canny enough to know that NATO would not forgo the opportunity to include them in naval and air exercises just to keep them close to the alliance. And wonder of wonders . . . after 40 years, France rejoined and was welcomed.
The nations of the center and east have been eager to both join the European Union and NATO. To their credit, they have met NATO commitments admirably (to the anger and chagrin of Russia); to the annoyance of the rest of the EU, their people have flooded western Europe looking for and mostly getting good jobs.
Which leads me to observe that Europe's current problems result in large measure from immigration. Before anyone raises the racist issues of Muslim immigration, there has been a great deal of internal EU migration from the former Warsaw Pact nations to the NATO nations for economic reasons. The nations of western Europe may not have liked it, but they have accepted and adjusted to it. In the hooraw over Muslim immigration, that salient and very important fact gets overlooked.
So, yes, i'd say the European Union will survive. I know of no attempted union which has had to absorb so many economic blows and still maintained its standards. EU countries provide health care, housing and educational benefits that the United States, Japan and China do not pay. I'd say that, in fact, they're doing admirably well. Greece shows itself up to be a nation of whiners who have been unwilling to play fair with their own government, and who have brought their own problems on themselves. It is to the credit of the EU that they have bitten the bullet on behalf of those lazy sons-of-bitches. Portugal and Spain, i suspect, are suffering from the burden of maintaining social systems which their already weak economies can ill afford. Catalonia has been the industrial engine of Spain for literally centuries (and i do mean centuries--since 1492, and before that, they were the economic engine of Aragon, for centuries before Ferdinand married Isabella and made somebody of himself). Franco treated Catalonia very shabbily, and in the process neglected the best opportunity Spain had for 40 years to build and to "grow" her economy. It's been an uphill battle ever since. Portugal--well, Salazar screwed everybody, and the Portuguese were content with right wing dictatorship and the stagnation of a traditional peasant economy. They've got a hard row to hoe, too.
The European Union reminds me the United States before 1787, when it was a clumsy, limping, ineffectively governed "nation" of bickering states, jealous of their petty sovereignties, mistrustful of one another, and content to have bad government under the articles of confederation if it would preserve the illusions of individual prestige and importance. Long, long ago in a thread about Europe forming a strong union, i pointed out the shifts by which the constitutional convention in Philadelphia reconciled the petty jealousies and puerile suspicions which crippled the Continental Congress, and created a unified nation by concessions to individual sovereignty (the electoral college and the Senate with its unique powers), and wrote that Europe will have to do something of the same kind if they want to truly unify themselves. My comments were ignored.
When you consider that the current system is like a continual boat drill with dozens of crabby lubbers who can't find the business end of an oar, it's rather remarkable that they do as well as they do. In large measure, that's thanks to France and Germany with their relatively robust and stable economies. The EU will not, however, be able to dance this reel forever, and they will be obliged someday to either make a real government for themselves, or go their separate ways. I don't think any of them want to contemplate the latter possibility.