Assuming I have some criticisms of the application of Islamic laws, why must I ask your permission to express them, and to hold political opinions in general? I'm sure that some of my opinions would be held offensive by someone, does that mean I have "offended a religion/culture"?
This was my first comment on this thread, and I'm not the one who submitted it. Read the usernames attached to the posts.
> if...you insulted that religion
As I said, it depends on my opinions and the definition of insulting - people might be insulted by what I say, I don't know until I've said it, do I.
In Liberal Theory (On Liberty, JS Mill) it is said that freedom of thought (believing something) and freedom of expression (expressing that belief, whether in a wordy article on political theory or a catchy, easy to understand cartoon) are so close as to be indistinguishable; since one cannot really claim to believe something if one cannot express it. You are trying to distinguish between the two; I don't think that's philosophically valid.
Additionally, you seem to be saying that you think it should be against the law to be rude. I will no doubt offend you if I say "how very English that sounds".
Offense is interpretation. This is fundamental to Liberal Theory.
In some cultures, some things are considered racist, in others they are not. see: "Black Person Toothpaste" http://en.wikipedia.org/wiki/Darlie (In China, a popular brand of toothpaste. In the UK, US, and I'd hope much of Europe, the name and the packaging would be considered extremely offensive[1].)
If "humans" don't agree on what's offensive (as I have proved with the toothpaste example), then something isn't "offensive" in and of itself; offense is an opinion about the object ("We think this opinion is offensive"). You can hardly convict someone of "causing our people to interpret something as offensive".
[1] although perhaps not in Italy... http://www.theguardian.com/world/shortcuts/2013/jul/30/italy...
And if they are so easily offended, this is not OP's fault.