Funny you should mention Greece... you do realize that their entire collapse was caused by a combination of criminals who retired from the Greek government, the ECB, and Goldman Sachs? And you do realize that the "Troika" was nothing short of a coup? Not much economics to discuss there - it was outright fraud and theft.
I think it is much more complicated than that, but the essential problem of Greece is that an economy that was used to an inflationary currency and a state that was used to cover its ill-controlled finances with extra loans in an easily obtained own currency (which was at the root of the inflationary currency), suddenly got propelled into a much stricter financial system, with a very low inflation currency (the Euro), where loans weren't tempered by inflation "on command". In fact, Greece was simply economically not ready to join the Euro zone, but this was done for essentially geopolitical reasons. Goldman Sachs accepted the mission to falsify the Greek books so that the political goal could be met.
In the beginning, the state and the economy continued to live like before, but with a much stronger currency, which lead them to believe in an apparent sudden wealth. Moreover, the Greek state borrowing money like crazy, was the feast of German banks ! Everything seemed to go for the best. Do you know that Greece, at a certain point, was the highest importer of Porsche sports cars per capita ? They spend themselves to ruins with the Olympic Games in 2004.
However, when pay day came, things became more difficult. The Greek state and the Greek economy were used to push debts away with inflation - this was not possible any more with the Euro. Their way of handling money was simply adapted to a highly inflationary currency, and their fast integration into a strong currency system made them live a lot above their means for a while, and put them into debt beyond what was reasonable.
Put the international banking crisis on top of that, and the story is complete.
Or maybe you just listened to the mainstream account and stroked your beard? How about Cyprus? Did you know that 50% of private citizen's bank deposits were simply stolen by the government to pay private bond holders (Goldman again, I believe)?
I agree, but this could have been solved in exactly the same way without doing that: putting a tax of 50% on all possession.
I'm always amazed at how people seem to think that the financial system is "stealing" them, while they pay 10 times more taxes than what they lose in the financial system. If inflation is a form of theft, then it is of the order of 2%. Nobody pays 2% of taxes. I pay around 60% or so if I count everything (social security, income tax, VAT, propriety tax, local tax....). I couldn't care less about those 2% or so.