Just like the US dollar, the euro is a single currency which is shared by 19 countries of the European Union.
That’s the official fiction. If the powers-that-be in the EU had really wanted it that way they could have had it that way. They would have needed only one central bank. There would have been one design for each of the various banknotes and one design for each type of coin.
Instead there are multiple country based designs for both notes and coins. Notes carry a serial number including a country code. There is one national central bank (NCB) per country plus we have the European Central Bank (ECB) . Whereas most currencies can be considered to be a two layer structure, the euro has a three layer structure. It can be best understood as a collection of tightly pegged but slightly different euros. The Bank of Greece (their central bank) can still print and create euros which they normally do with the approval of the ECB. That approval has been recently withdrawn. So what happens if they create euros without the ECB’s approval? The ECB can only refuse to guarantee them on a par with other euros so instantly the Greek euro would float.
All Greek banks whether domestically owned, or foreign owned, rely on the BoG for their liquidity. So the closure of the Greek banks, including all foreign owned ones, has nothing to do with their financial viability, but everything to do with the inability of the BoG to provide the euros they need to function.
If the euro were a truly single currency the ECB would not be able to isolate Greek banks and their account holders in the way they have. The banks could open tomorrow if the BoG started to create euros again. And indeed they should, preferably with the support of the ECB. The ECB has a duty to all Greek euro holders just as the US Fed has an obligation to all holders of US$. It would be inconceivable that any political dispute between the Federal government and , say , the city of Chicago would result in the residents of that city being denied full access to their bank accounts.
If the BoG issued euros without ECB approval then we’d have a new currency. The Greek euro. Just what would be the status of all previously issued euros, both digitally and physically created would depend on the willingness of the ECB to guarantee them. It would be legally messy but it is a quick solution to get that new currency.
In the EZ, bank depositors, except of course in Greece at the time of writing, can costlessly shift euro deposits from one bank to another anywhere in the zone. Any depositor of an Irish bank, say, can move their money to a German bank. This requires the Central Bank of Ireland to obtain reserves that get credited to the Bundesbank, the central bank of Germany. If deposits tend to flow from the poorer nations, to Germany in particular, their central banks go ever more deeply into debt to the ECB to obtain reserves that accumulate in the account of the Bundesbank.
As recent events in Greece show, it makes no sense at all for anyone to hold any amount of money in the peripheral banks. The sensible thing is to shift it to a German bank for safe keeping. This is not doing the Germans any favours. It is simply the best way of forcing those most in favour of the euro to accept full liability for euros held by all Europeans. So logically nearly all euros should end up being German euros anyway!
Is this yet another fundamental flaw in the architecture of the eurozone? The ECB has to guarantee the liabilities of the peripheral NCBs to hold the system together but what if any country defaults? They will be rid of their National debt at a stroke and can then start afresh with a new currency. The ECB ends up with the bill, which means the rest of the eurozone. Ultimately if everyone else defaults it is Germany, or the last country left in the system, which has to pick up the tab for everyone else.
The Germans should be extremely worried at the prospect of Greece defaulting to be followed by whoever may be next, then whoever is next after that. At the first sign of any repetition of the Greek experience, savers in the less safe regions of the EZ will, if they are sensible, shift the bulk of their savings out of their local bank and into German euros. They should make plans for doing that now, while there is still time.