- Fiscal Union (i.e. taxation and expending must be made at the EU level, like the creation of a EU income tax).
- Massive wealth redistribution within states (i.e. a huge portion of the revenue of states with greater economic problems must come from Brussels).
However, this is pretty much impossible in a world divided by borders. Italians and Greek will not be willing to be taxed by Germans and Germans will not be willing to send their money to Greeks. As I have been saying for years, the idea of "country" is probably the greatest global problem. Citizens of EU citizens should give up their nationality to become Europeans first and let them be taxed and financially managed by Frankfurt and Brussels. This change would probably start from Southern Europe as they are the ones most affected by the current situation. If Southern Europeans do not accept to give up their nationalities to become European first and Italian, Spanish, or Portuguese second, more financial pain will follow.
However, I think that nationalities are still too strong in Europe. When abroad and “asked where are from?” Europeans give their countries as the answer. No one says “Europe”. No one is really talking about going to the Olympic Games or Soccer World Cup under a European flag. People cheer pretty strongly for their own countries and that’s it. There is no United Nations of Europe and unfortunately, we will probably never be during our lifetime. Any change in the direction of a United Nations of Europe will likely be pushed back mainly by older generations and people with lower levels of education, possibly encouraged by populist leaders. Southern European economies will be most likely stagnate for decades (much due to brain drain and capital flight) and the euro as we know it today will eventually collapse.