Yea man, humans are tribal beings. It's wired into our being. This group of people is always going to hate that group of people whether they have the same god or not, whether they get their life instructions from a Qu'Ran or a Talmud or Bible. Erase all of that shit and they'll still align themselves with their ancestral people.
Even in the U.S. where religion is becoming less and less important in all walks of life people still find reasons to hate each other.
"Those fuckers eat Kneidlach killl 'em"
"They don't like our matzo ball soup, yet they eat dawali - can you believe they stuff grape leaves? KILL EM"
Idk something like that - they'll always find a reason to fight. Religion may be an accelerant but it certainly would still be bloodshed over the past millenia of infighting between groups of people fighting for their people to be on top of the pile.
They all need a strong dose of MDMA in my humble opinion. But even then, I have little faith that small area will ever know peace until one tribe moves or is eliminated.