Back when Greece joined, Europe was still divided. When they became a democracy, it made sense to pull them in the Western camp, and away from theAmeri, erm, dictatotial camp.
The EU has functioned as a great sausage - it bolsters the democratic parties in countries during and after dictatorships with the promise of a viable future as part of a wealthy democratic bloc. It is a great instrument of pressure - reform into a democracy and you get to join. It worked wonders in Spain and Portugal, and later Eastern Europe. Not just before 1989, but also in the transitional phase of the 1990s. Most in Eastern Europe did not lapse in the nineties and naughties into some sort of semi-dictatorship like Byelorussia, but slowly transformed themselves into functioning democracies. Which is not as self-evident as it appears.
As such, it was a historic necessity that Greece could join. Dwarfing the current events.
But Greece has not been a good partner. Too corrupt, too much dependent on subsidies. Too much forever following its own agenda. Sometimes downright obstructing Europe. Like Greece, Portugal never really took off economically either, like the succes stories Spain and Ireland did. But at least Portugal is on the whole a more reliable partner. (Or maybe I just feel more culturally connected to Portugal than to the Balkan).
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