Generalities to realities.....right off the top of my head I can state the strife that has existed in
Ireland between the Protestants and the
Catholics, or the strife between the Buddhist and
Muslim Rohingya, or Armenian Christians and Muslim Azerbaijani. I was talking about religion as a whole as a underlying reason for wars and strife. Regardless the problems run much deeper in the ME among themselves was the point. Here's some examples I ran across, I can find you plenty more if you still want to argue the point.
Shia and Sunni:
Sunni Islam and Shia Islam are the two major denominations of Islam. Their division traces back to a schism following the death of the Islamic prophet Muhammad in the year 632AD. A dispute over succession to Muhammad as a caliph of the Islamic community spread across various parts of the world, which led to the Battle of Jamal and Battle of Siffin. The dispute intensified greatly after the Battle of Karbala, in which Hussein ibn Ali and his household were killed by the ruling Umayyad Caliph Yazid I, and the outcry for revenge divided the early Islamic community.
In recent years, Sunni–Shia relations have been increasingly marked by conflict,[14] particularly the Iran–Saudi Arabia proxy conflict. Sectarian violence persists to this day from Pakistan to Yemen and is a major element of friction throughout the Middle East and South Asia.[15][16] Tensions between communities have intensified during power struggles, such as the Bahraini uprising, the Iraq War, and most recently the Syrian Civil War[17][18][19] and in the formation of the self-styled Islamic State of Iraq and Syria that has launched a genocide against Shias.
https://en.wikipedia.org/wiki/Shia%E2%80%93Sunni_relations
Alawites:
Alawite beliefs have never been confirmed by their modern religious authorities.[64] Alawites tend to conceal their beliefs (taqiyya) due to historical persecution.[17]
During the Syrian Civil War, the Alawites have suffered as a result of their support for the Assad government against the mainly Sunni opposition, with up to a third of young Alawite men killed in the increasingly sectarian conflict.[58] Many Alawites fear a negative outcome for the government in the conflict would result in an existential threat to their community
https://en.wikipedia.org/wiki/Alawites
Yazidis:
This belief has been linked by some people to Sufi mystical reflections on Iblis, who also refused to prostrate to Adam, despite God's express command to do so.[37] Because of this similarity to the Sufi tradition of Iblis, some followers of other monotheistic religions of the region identify the Peacock Angel with their own unredeemed evil spirit Satan,[38]:29[26] which has incited centuries of persecution of the Yazidis as "devil worshippers".[39][40] Persecution of Yazidis has continued in their home communities within the borders of modern Iraq, under fundamentalist Sunni Muslim revolutionaries.[41]
Beginning in August 2014, the Yazidis were targeted by the Islamic State of Iraq and the Levant in its campaign to rid Iraq and its neighbouring countries of non-Islamic influences.[42]
https://en.wikipedia.org/wiki/Yazidis
These are just some paragraphs taken from the articles. Some explain the origins of the conflicts going back hundreds of years up to today still. These are just some, like there is different sects of Sunni that hate other Sunni over a break off of some minute difference in observation of religion, same for Shites. That's what people don't understand is the mass amount of the littlest minute difference has sprung forward untold numbers of splits and they are willing to
persecute and kill each other it.
Then there was ISIS who just plain wanted to kill anybody and everybody who wouldn't adhere to a strict Islamic observance.