The bloody assault on the offices of the French satirical magazine, Charlie Hebdo, can only provoke the most profound revulsion. This was a dreadful terrorist atrocity that has claimed the lives of at least 12 innocent people.

Our first response must be to mourn the victims, four of whom were the magazine’s well-known cartoonists and two of them police officers. But this was more than a human tragedy. It was a calculated act of intimidation, an attack on the freedom of expression that is the pillar of any democratic society. It was designed to seed an insidious form of self-censorship. It must be roundly and defiantly condemned.

Nearly a decade has passed since a Danish newspaper first attracted the ire of Muslims by publishing cartoons that lampooned the Prophet Mohammed. What started with peaceful protests and consumer boycotts has steadily descended into violence. This is not the first time Charlie Hebdo has been attacked for publishing its own cartoons satirising Islam. Its offices were firebombed three years ago.