Is not the territory.
The real reason is really to exterminate the Palestinians because they are real the descendents of Hebrews and Canaanites, unlike Ashkenazis who are genetically europeans and Sephardis who are mostly of maghrebi admixture.
So their existence threathens the whole myth of Israel.
Otherwise, Israel could have taken Gaza years ago, but the real goal is to exterminate the Palestinians really.