Why is there so much focus on attacking Judeo-Christianity in the R&S forum?

I'm not Christian, but I have to wonder why there's this obsession with attacking the Bible and/or the Torah. It looks weird. Religiosity is at an all-time low in the Western world, yet religious fanaticism is alive and well in the Muslim world. Why don't you spend your time attacking things written in the Qu'ran? Modern Islam is about as fanatical as Christianity was 1,000 years ago. Most people from Christian backgrounds don't fully agree with everything written in the Bible. The Muslims, on the other hand, will want to kill you for drawing a cartoon about Mohammad.