When G.W Bush commanded attack on Irak, killed maybe million of moslems in the name of Weapon of Mass Destruction (no proof of existing though), many moslems hate christians because of stereotyping them with Bush.
When Kouachi brothers attacked Charlie Hebdo and killed 14 people, many christians hate moslems because of stereotyping them with Kouachi.
Not all christians are like Bush, and not all moslems are like Kouachi brothers.
Lets be wise.