I guess it all depends on your point of view, snapshot.
After all, we were constantly told last week that there were up to 25 000 "Lebanese Australians" in Lebanon at the start of the crisis. A percentage were tourists, and some were visiting family, but there were plenty who had returned "home" to live permanently - although whilst retaining their Aussie citizenship and passport of course.
As soon as there was trouble, plenty of these people started screaming for the Australian Government to come and evacuate them, and complained loudly when it wasn't fast enough for their liking. Anyone who dared to question whether it should be the Australian taxpayer's responsibility to pony up for the evacuation of permanent residents of another country was branded with the usual "racist" and "anti-multicultural" tags.
For what it's worth, I find dual citizenship of any sort (except
perhaps New Zealander / Australian) to be impossibly conflicted. In my opinion, once you take Australian citizenship, you should have to renounce the citizenship of any other country. I don't care where you or your parents were born, if you want to be Australian, that's where your allegiance must lie henceforth. I've got no truck with Australians who want to go overseas to fight for anyone else - whether we're talking about Serbian Australians going "home" to fight the Bosnians, Israeli Australians going off to fight the Arabs or anything else. And don't even start me on traitors like David Hicks who have no other citizenship (at least at that stage) but who head off and sign up for non-state terrorist groups like Lashkar e-Toiba and Al-Qaeda.
All of this is in no way to suggest that migrants have to forget where they came from. The multicultural element in this country (and that's truly what it is, not a plurality of monocultures like in many European countries) is what makes it such a fantastic place. Preservation of those cultures is hugely important - and I don't even
really mind if those of Italian descent feel they have to support the Azzurri against the Socceroos.
But once you take out the papers of citizenship, this country (and no other) has claim on your formal allegiance - and you have the right to expect that allegiance to be returned in the form of help when you need it. But that mutual obligation removes your right to go and fight for someone else. If you feel strongly enough, then go for it - but take out their citizenship instead of mine when you do it.