2 Possibilities: a) Because they are not Jews. b) Because they don't support an ideology (expansive Zionism), that doesn't leave any space for compromise, and whose ultimate aim still is to push the native (Palestinian) population in the neibhourhood out of their (West Bank) land. Make your choice, but I assume most reasonable people around the world (including many Israelis, at least from the political left) won't have to think twice, in order to find the correct answer.....
Ya'alon okays administrative detention of Jewish extremist suspected in church arson (Haaretz)
from the article: Think tank: Israel faces global delegitimization campaign