One currency, 27 agendas. 27 different sets of economic problems to solve. Interest and exchange rates were the ultimate get out of jail free card for policy decision makers. So now what do you do when your country becomes uncompetitive and you run out of money. There are no macro economic fine tuning tools available to you. It's just like you and me with no job and your house dropping in value. So the answer is you borrow more, get state support or default.
The euro zone has benefitted the stronger economies, and probably no coincidence the ones with better transportation systems sitting centrally in Europe. They have more more accessible markets.
No prizes for being right. What do we do now? Break it up or devalue the euro and everyone will lose money. Ouch. Luckily I work in an industry that is essential to the economy. Marketing and advertising ... May be not then.