Grexit would be the beginning of the end of the Eurozone.<p>Once you set the precedent that a country can leave the Eurozone there will be a day that things get tight and then Spain will leave or Italy will leave -- somebody who is big enough to bring the whole thing down. It might take 10 years or 30 years but it will be inevitable.<p>Also Grexit will sour Europeans on the idea of any expansion so there will be no possibility of the Euro zone pushing further east which would be a great counter against Russian aggression.