This is precisely what JS Mill and other political philosophers meant when they discussed free speech and the need to protect it. In a true marketplace of thought and speech, we are all free to advance our opinion and ideas, and to accept or reject those of others. Yet we have become a culture where speech is perceived as having the power to 'cause' behavior. The truth is, in a democratic environment, no one's speech has more of a place in the market than others. We are forgetting our Western foundations:
“If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind.” ― John Stuart Mill, On Liberty
“The peculiar evil of silencing the expression of an opinion is, that it is robbing the human race; posterity as well as the existing generation; those who dissent from the opinion, still more than those who hold it. If the opinion is right, they are deprived of the opportunity of exchanging error for truth: if wrong, they lose, what is almost as great a benefit, the clearer perception and livelier impression of truth, produced by its collision with error.” ― John Stuart Mill, On Liberty
So, to your point concerning 'inflammatory' speech, what is the purpose of protection of speech, specifically dissent (which Charlie Hebdo's cartoons essentially were) if not to guard against tyranny and oppression of the People? How do we develop an ability to discern the merit or lack thereof of speech that we encounter, if tyrants are constantly shutting down the marketplace and demanding strict adherence to their thought and their speech, under the mantle of "I'm offended"?
'Inflammatory' rhetoric is everywhere, every day, different day. And in my view, the inability to tolerate or ignore or shake off the speech and its impact, says more about the group who is always incensed and seeking to silence, than it says about the content of the speech.