Quote Originally Posted by Ocelot
they are very similar, you are correct, but the reasons for them being violent towards each other throughout time are probably exclusively related to who was/is in charge of the separate regions. They feel they are the right ones, like everyone else is wrong, and they feel they must purge the filth from the world. neither side bothered to read the other side's texts, and neither of them care for a negotiation. there simply can be only one religion, only one true God, in these people's eyes.

I'm sure the thought never occurred, and probably still will not, due to pride, that their religions are one and the same, with only a language barrier to separate them.
Not totally true, if I understand correctly Islam does recognize Jesus as a prophet but not the Messiah. Typically Islam is respectful of Christianity but the sentiment is not returned since Christianity does not recognize the Prophet Mohammed. You are right with the "We are right you are wrong" view from either side but I think the harsh criticism and discrimination that Islam receives is unwarranted.