I could do nothing except repeat what others have said. Why would anybody want to read endless posts of condemnation?
It might be worth reading if somebody supported the cartoon and a spat ensued, but I don't think many people will do that.
FWIW, when the CH were murdered, I didn't sign up to the 'Je suis Charlie' movement. While I could never condone the murders, I also felt that the cartoons which provoked the outrage were vile and unnecessary. I have never supported complete free speech, which is how many people justified those cartoons. At the time, I got quite a bit of flak for having those views and generally kept my head down.