It has nothing to do with ancient history. It has to do with modern history. Israel's right to the land in controls rests on its victorious arms. All of the states of the region have only been independent since the withdrawl of the great powers after WW II. All of them were subjects of the Ottoman Turks before WW I, and still would be but for victorious British arms.
In the corporeal world, a right over a territory means victory in the last war fought over that territory. If various Arabs don't like the verdict of the last war, they are welcome to lose a new one.
Well said, and accurate.