I bet not many people can remember the "Danish Cartoon" incident back in 2005 but it was a massive red flag warning to the "West" about what was to come from Islamist extremists (and many other kinds of extremists)
It's relatively easy to whip up a frenzy of "offence" and then to target that toward violence when people are largely ignorant (i.e. uneducated) and feeling oppressed, we see this kind of thing all over the place nowadays! Isn't it ironic that since 2005 the "violent mob" strategy, from frothing (Islamic) flag burners to gun toting (Christian) abortion clinic botherers, seems to be just the default way politics gets done these days.