Considering the Pope basically said they got what they deserved for insulting muhammad, I don’t blame them.
Bill Donohue came close to saying the same thing.
Related threads:
MUSLIMS RIGHT TO BE ANGRY
Pope on Charlie Hebdo: There are limits to freedom of expression when faith is insulted
Before last week's attack the magazine had published cartoons portraying the Holy Trinity in sodomy and had labeled Jesus as the "child of sin". Their disdain for Catholic support stems from their disdain for Catholicism per se and predates anything +Francis or Donohue said.
As the above link makes clear, this had resulted in multiple lawsuits filed by Christians. They're essentially the poster children for the new Europe; secular, libertine and godless. A more aggressive French equivalent of Bill Maher.