Delusional?
Apparently you don't believe that the bible is God's written Word and His promises in that written Word are always kept. If you did you would know that every square inch of the land between the Nile and the Euphrates rivers is owned by the descendants of Abraham. The vast majority of that land has never been occupied by it's Israeli owners, but it will be at some point in the future when it's rightful owners realize that their promised Messiah is Jesus and accept Him as Israel's Lord and King.
Since Israel won the war, they can occupy the territories and under international laws they are required to establish laws for the Palestinians. So for almost 50 years they have had the laws and the laws have done a lot of evolving.
Under international law Israel is allowed to seize any lands that they need to administer the territories, but they are not allowed to seize lands on which Israeli citizens can settle. The first Israeli settlements in the territories after the war were ruled illegal by the Israel Supreme Court.
Israel would then utilize "Mawat Law", an Ottoman Empire law that allows unused land beyond a certain distance from a settlement to revert to the state, in this case Israel, afterwhich the land can be used for settlement.
There are a higher grounds that are rocky and not suitable for farming and consequently unused, although the lower lands surrounding are likely farmed. Because they are higher ground, they are easier to defend, and well suited for settlement.
A few years ago a documentary was produced in Israel examining Palestinian law, which was titled "The Law in These Parts". Its a series of interviews of men who were military administrators, lawyers, and judges who devised and implemented the laws thru the years and decades.
It can be found on YouTube and is informative, but it is not in English so you have to read the subtitles.