Remember, Mohammad was tolerant of all the worshippers of the one true god... including jews and christians. All three belong in the first house. Don't confuse the "names" used by the local language as having been meant to be exclusive.
It is the modern fundamentalists (of all three religions) who preach hate for the others.
Same answer. Modern fundamentalists are so self-rightious that they even denigrate sects of their own religion over minor differences. I've even attended christian services where the minister denigrated people from his own congregation who attended the alternate, "more convenient" time, to attend services.
In my opinion, fundamentalists are just too full of themselves and are incapable of tolerance.