"Free speech can't just apply to those you agree with," the editor of Spiked Online, Brendan O'Neill, once said. Politically correct speech does not need protecting. The United States' First Amendment exists precisely to protect the minority from the majority and to protect unpopular opinions from those who would silence them.
On March 2, French prosecutors decided that Marine Le Pen should be prosecuted for drawing attention on Twitter to the atrocities committed by Islamic State. They apparently decided that Le Pen's message, even if factually correct, should not be heard.
Le Pen's "crime," the prosecutors allege, is that in a series of tweets, she posted disturbing images of victims of Islamic State, thereby exposing the crimes against humanity that group have been committing in the Levant.
Presumably, these were potential dangers about which she thought the public should be aware.