I've already noted that the Greek economic crisis was inevitable, and the result of a series of logical errors, all driven by neoliberal economics.
Perhaps the most significant of all of these was the idea that markets were more important than states.
The EU ideal was to create a 'common market'. But simple freedom from tariffs became something much more potent - and dangerous. It was taken over by the idea that market was by itself the most important part of the European ideal.
Of course nationalism has had a bad history in Europe. And of course moves to ensure greater political cooperation were always going to be, and are, welcome.
The fact is that markets are not more important than states. The state has much more to offer to the people of any country than its market ever can. The wrong priority was set in 1992. The wrong priority has remained. And now we are paying the price. A country is collapsing because of the demands made upon it by a market which was always going to be unsustainable. This is the ultimate neoliberal folly: nothing but the market counts according to that creed (for a creed it is, since it has no logical foundation). That creed does not, however, value democracy, the rights of people to self-determination, cultural differences, or respect for tradition.
If Greece fails because the demands of the market are met then it is not an isolated problem: it is indication that the state is secondary to the marketplace, and that's not just a cause for concern, that calls for real fear, because the reaction will be severe.