and palestine is within israel. it is under occupation after the wars. it is not it's own country. it is a stateless nation.
Yes, historically-sppeaking, the territories that are now reffered to as 'Palestine' are an integral part of the land of Israel. It has been re-occupied now, as you've said, and so the people living in those areas are not Israelis, and their land isn't part of the new state of Israel. Building a wall between them and the Israelis is just like establishing a border between any two countries.

Now, don't talk to me about humane values. Those are precious and dear to me - but not more than the value of protecting human lives, especially on my own side. I'd rather have a thousand screaming but very-much-alive enemy terrorists, then one dead innocent.

There's a saying in Hebrew, that could be translated like this: "One that shows mercy for the cruel, will end up being cruel to the merciful." Being kind and righteous is all perfectly well - but there are times when you have to show your darker side. Necessary evils to protect the most precious thing of all - human life.