You are forgetting religion is a personal worldview of an individual. Depending on the blasphemy an attack upon religion becomes an attack on the individual as the individual believes in said religion. If I call a religion stupid this reflects upon the individuals that believe as stupid, gullible, ignorant, etc. Toss in a lot of people find self-worth in religion also means you attack the value perception of those individuals. Ergo Charlie Hebdo and Innocence of Muslim reactionary attacks.
I strongly disagree. People try to say the same thing about nationality, but I find it to be just as wrong in that case.
If we cannot criticize religion, if we cannot point out its flaws (as well as its strengths), then we simply do not live in a free society. those who struck out against Charlie Hebdo were criminals, pure and simple. They were striking at a basic freedom.
Being offended is a crime to many. This is not unique to religion.
See the above
Being offended should not be a crime. It is impolite, and anti-social in some cases, but it should not be against the law. Sticks and stones break bones, but names don't. There is a significant and real difference.
Now, if you go further and deny loans based on your biases, or deny legal opportunities, or otherwise deny civil rights, then there may be a crime. But simply being rude should not be. And, at most, blasphemy is rude. Often it is justified criticism that the religious authorities simply want to stop. In that case, it should be encouraged.