I'm Jewish and it's an interesting and pretty horrible history. Basically, for a thousand years and more, if you're Jewish, you swing from one genocide or massacre to the next. There are rising fears among my family because of the increase in anti semitism across Europe. I think, in the case of Israel, it has an effect. If you've spent pretty much every single generation for the last ten centuries, at the minimum, being oppressed, slaughtered, tortured, killed or imprisoned, then it's understandable for there to a backlash. Not that it makes Israeli policies right, but they are surrounded by people who want them dead. All of the Middle East, but for them, want them dead, and it's convenient that many of them have enough power to, quite soon in the future, act on that desire.
I agree it isn't Islam itself. Religion has been at the centre of violence since it was invented. It is more dangerous in many ways due to the technology we have around, but I'm sure the Crusaders would have done the same. Every religion has oppressed or killed people at some point imo- whether through genocide and harming people who aren't their religion, or through misogyny or homophobia or whatever as part of their religion. Buddhism, Islam, Christianity, everything. It is a rallying point, a very useful one. It's like with the Scottish Independence, there has been minor violence on both sides, and I don't think that's because of the referendum, it's because there are arseholes and their cause means they have a reason, or allows them to feel good about themselves doing it, whether they realise that or not.