I've seen support for Israel among the mainstream political sphere throughout my life, but I think you're right in that even people with support for Israel aren't extremely invested in it aside from radical Evangelicals. It was easier for the propaganda machine to discredit Palestinians and minimize the horror of Israeli attacks in the past, I don't know how a reasonable person could see any coverage going on today and think the IDF are the good guys. Even if they were right overall in their claims to the land their actions are clearly horrific.