On second thought, I can actually imagine a successful Juve with a core of Italian players, if by that we understand some 5 Italians in the starting XI and some other Italians for the bench.
There aren't many quality Italian players right now, but a team that has Buffon, Bonucci, Chiellini, Aquilani (?) and Cassano can actually do very good if the other 6 are also quality players. As a matter of fact in the last decade, pre-Calciopoli, that is the number of Italians we usually had in the starting XI. 4,5 or 6 quality Italian players + quality foreigners.
But I can't see who of those other 6 will be Italian. With Pirlo, De Rossi and Balotelli you end up with names of quality Italian players, and those three will not play for Juve.
We must act smart. If we do, in the end we can satisfy everyone. The ones who want to keep the Italian traditions will still have a good number of Italians in the team, while the ones who aren't really interested in the nationality of the players and simply want quality, will get their quality team.