The way I look at it, pretty much every race in the world is where it is because of 'Right of Conquest', the Romans pushed out the Celts, the Americans pushed out the Native Americans etc, it's an ongoing theme in history. History has never been famous for being 'Nice', particularly to the pushee, as opposed to the pusher.
Does any race have a 'Right' to be where it is beyond its ability to hang on to it, if all it took were bits of paper, why spend billions per year on defence budgets? And that's the crux of the matter, it's not about whether it should exist, that's looking at it from the wrong perspective, it's a question of how Israel, now it is established, interacts with the surrounding cultures, and how those cultures can be bought, if not into harmony, which I doubt, then at least to a less abrasive dislike of each other.