They have them because they are scared, and they should be scared because of all the wrong the Israeli government is doing. What goes around comes around, and when Israel gets whats coming to it, I will be smiling from ear to ear.
Netanyahu certainly would have no qualms at all about exterminating the Palestinians. And even if they tried, there would be severe repercussions for doing it, so what they are doing is isolating them and pushing them out of their own country, its the most they can do to them and still get away with relatively unscathed. Israel has its own Hitler with Benjamin Netanyahu, the only thing I would suggest he do is grow a mustache.