When it comes to Islam and terror, the fine folks at Fox have generally taken the view that Muslim terrorists are representative of Islam as a whole. However, when it turned out that Breivik (the person allegedly responsible for the terrible murders in Norway) claimed to be a Christian, the fine folks at Fox rushed to argue that he is not a Christian.
The main argument put forth by the fine folks at Fox is that a person who truly accepts Jesus would not engage in such horrible behavior. Naturally, Muslims who are not terrorists have argued that true Muslims would not engage in terrorist behavior. On the face of it, if the argument holds in the case of Christianity, then it should also hold in the case of Islam.
The obvious reply is to argue that while a true Christian would never do such things, such horrible acts are perfectly consistent with true Islam. The challenge is, obviously enough, to prove both of these things.
It will not do to point to the actions of those who profess the faiths. After all, people professing to be Christians have done terrible things as those who have claimed to be exemplars of Islam.
Turning to the holy books as evidence is a better approach, but not without its flaws. While the writings of Islam seem to allow and even endorse terrible things, the same is true of the Christian texts. As such, turning to the texts hardly seems to achieve the goal in question.
It can be argued that the violent content in the bible is either not an expression of the true essence of Christianity or that (to steal a bit from True Lies) true Christians only harm bad people (and thus are justified in doing so). In contrast, it must be argued that violent content in the Islamic writings is an expression of the true essence of Islam and that harming the good and the innocent is perfectly consistent with Islam. If this can be done, then the fine folks at Fox can consistently brand Muslims as terrorists while insisting that no Christian can be a terrorist.