A frequent tactic of modern religious believers -- evangelicals in particular -- is to contrast death counts between believers and atheists, comparing the hundreds of years of religious wars against the 20th century totalitarian systems that murdered millions of people for the sake of atheist ideologies. It would be easy enough to characterize this most recent spate of violence in Israel as a Jews vs. Muslims religious cage match, or the ISIS insurgency as Sunni vs. Shi'a internecine bickering.
The root of these issues are really just the usual old things -- power, control, water, territory. Religion is part of it, sure, as are culture and history, and the inability to drop a fucking grudge. But it always comes back to monkey killing monkey over pieces of the ground.