You want to mention the crusades and probably the Spanish inquisition, but don't you know that one of your own "prophets" Sam Harris, has admitted that no one following the explicit teachings of Jesus Christ in the New Testament has ever committed murder, genocide, or gone to war based on those teachings.
People and groups throughout history have done just like you have and taken biblical texts out of their contexts to attempt to support their own murderous hearts and justify their own sins.
People calling themselves Christians and claiming the texts of the bible told them to murder or go to war is a lie and indefensible because Christians are told to do no such thing. That is why atheists like Sam Harris, who actually understand logic, reason, and sound argumentation do not use that line of argumentation against Christianity but only against its misuse and abuse.