Uhm, are you really claiming those two countries weren't corrupt before the EU?! Afaik, both are classic cases of the Mediterranean client-patron culture? (At least the south of Italy.)
My original point was that to make a country a nice place today is not rocket science, the failures either seems to be an ongoing conflict -- or corruption.
Afaik the methods to stop corruption isn't that hard to design, the hard part is to get a political class to implement them. To do it from outside is impossible without an invasion, you have to get the population to pressure the criminal thieves (a.k.a. politicians).
(I guess 'fulafel' is a naive Swede who grew up believing his own media, like I did. That is why I bother with this.)
Disclaimer: No political science education, just a hobby to read to try to understand the world,