No Israeli thinks their country's legitimacy is owed to some organization set up by countries which did not even almost exist yet when they first lived in that country (over 3,000 years ago). Even after being conquered more than a thousand years after being established, by the early Europeans (the Greeks and then the Romans), after their country was destroyed mercilessly by those early Europeans, 2,000 years ago and most of the  Jews dispersed to Europe, nevertheless many Jews remained there, and in fact no other country was established by any other nation there in the absence of a Jewish state. Of course the ArabMoslem invaded 1,500 years ago in their jihad, and now they have a large presence in the land, but even they never set up a country there during this 1,500 years, it was a part of some remote province. And in any case, they lost it just as they got it, in war. It is the Jewish country, the Jewish homeland, now, as it was 3,000 years before the UN was invented.