Many of the anti-islamic rhetoric im hearing is about how Jesus (pbuh) has always been made fun of, so why is it such a big deal?
Well, this is the reason. It is sad that i have to point this out but i need to in order to answer this question.
Not even Muslims of the lowest order have ever even so much as POTRAYED Muhammed (pbuh), let alone a 'humourous' cartoon animating him. In history
there has never been a depiction, represention, painting WHATSOEVER about him, partly because of what had happened as a reaction to Christianity. People during both Jesus (pbuh) and Mohammed's (pbuh) time began depicting them by drawing pictures of them. This would indeed lead to idolatry, and a false representation of what were pure beings, so Mohammed (pbuh) asked to cease anything to do with a drawing of himself so as to prevent idolatry. If you see paintings from the middle ages of Muhammed (pbuh), you will indeed see a fire covering his face, so as to not blaspheme his holy image. Representations are depictions according to ONE sole being's perspective, and therefore are UNTRUE, and you will find this, not as Islamic dogma, but as part of postmodern arguements about 'realism' (i emphasise this to show you that Islam is not all backward).
What had happened with Christianity is that people began to try to make sense of the concept of God, and to preserve the 'white' image of Jesus, they began drawing representations of them. The human brain, unfortunatley, as we saw in with Moses (pbuh), is not equipped to understand even so much as the essence of God, and God's humanisation was therefore a representation according to what the human brain can understand.
What im trying to say is, the Christian Jesus, God, and Mary, are as a result, icons. Their images have been circulated so much that they are simulacrum. Islam has called for the end of idolatry, and in so doing, did not seek to represent Mohammed (pbuh), and this is why it is difficult for some to see his image as cartoon.