The Charlie Hebdo tragedy is terrible, there is not a way to justify violence and to killing people. But, in the other hand, is it justified to simply laugh about other beliefs, even when you are not doing points on any issue but simply mocking on people because your ego says you can?
Sadly to say is that one of the Charlie Hebdo survivors insulted most people saying “We vomit on all these people who suddenly say they are our friends.”
So, is this the way they give thanks for some world support? Are they paranoid thinking everybody is always wrong and they are right?
We need liberty of expression, but also responsability. I'm afraid these type of cartoonist/artist are spreading too fast: without rules you can't know your limits and without limits you don't know were to stop. This is a basic principle that now seems to be forgot. Realizing about limitation is not really bad because make you think and work harder, instead to take the easy and (in various ways) tragic easy path of insulting and making fun of everything.
Really, humor is a very clever and difficult task. But making fun of what it is sacred for most people, just because you can or because you are going to get a couple ephemeral laughs, shows your lack of knowledge and lazyness. Sergio Aragones, Quino, Charles M. Schultz, Jim Davis and many others successful on cartoons and humor are an example of boundaries broken with clever, funny and hilarious gags year after year.