Okay, i think you are honestly not aware of the reasoning.
Think of it this way. We are the kids of the same neighborhood, Egypt, Greece, Turkey, France, Libya, etc... Now, two kids don't like each other much, they be friends with other kids. Sometimes, friendships change the kid with you, now hangs with me and vice versa. But we both know we won't knife each other. Maybe, we will yell each other, maybe throw a few fists but that's it. Than you go and be best friends with the only drug dealer, killer in the neighborhood that nobody really likes. Now, i gotta think, is he going to knife me?