The jihadist assault on Charlie Hebdo a year ago was more than an act of mass murder. It was a gruesome test of Europe’s commitment to Enlightenment values. It was an attempt to enforce, through a summary execution of heretics, the idea that there should be limits to the liberty to speak and rile, and that anyone who breaks these limits will be punished. It was a question mark, written in satirists’ blood, demanding of all Europeans: “What is more important: the right of cartoonists and hacks to say whatever they like, and offend anyone they dislike, or the right of religious groups to feel respected?”

Tragically, many Western liberals gave the wrong answer to this question. They effectively agreed with the killers that scurrilous speech, especially of the allegedly Islamophobic variety, should be kept in check, and ideally not expressed at all. They expressed in pained op-eds what the murderers had declared with brute force: that it’s wrong to sacralize freedom of speech at the expense of the self-esteem of minority groups.

In the weeks after the massacre, so-called liberals implied that Charlie Hebdo’s staff brought their murders upon themselves. A writer for The Guardian hoped for a new post-Charlie era in which we’d all remember the “obligationsupon those who wish to live in peaceful, reasonably harmonious societies”, primarily the obligation to “guard against the understandable temptation to be provocative”. In other words, if you don’t want to have your head blown off, then censor yourself, bury your beliefs.

Such craven demands for self-silencing were widespread. A Financial Times columnist slammed the “editorial foolishness” of Charlie Hebdo. The mag wasn’t “strik[ing] a blow for freedom” by mocking of Muhammad — it was “being stupid”. You could picture him at the scene of medieval executions of earlier blasphemers, shouting as the flames licked their bodies: “This is what happens when you say stupid things!” A columnist for the left-leaning New Statesman wrote a tirade about “free-speech fundamentalists.” He insisted there are speech lines that “cannot be crossed”. It was exactly what the killers thought, only expressed more eruditely: “Don’t cross the line, or else”

The post-massacre illiberal liberalism reached its nadir when big-hitter novelists complained about American PEN giving a courage award to Charlie Hebdo. They said it was “inappropriate” to decorate a magazine that mocked Islam. Apparently freedom of speech should only be used for ‘nice’ ends, not to make challenging statements. Which would not be free speech at all, of course: it would be sanitized speech.

The moaning novelists and apologist columnists seem not to understand that freedom of speech, by its very definition, must apply to all or it does not exist. A society in which we are not free to draw a picture of Muhammad with a bomb on his head is not a free society.

Western liberals effectively did the killers’ dirty work; they wrote the chilling, illiberal manifestos that the murderers didn’t get around to writing.And they dealt a devastating blow to the Enlightenment itself.

The Enlightenment, coming after the Inquisition, was fundamentally about insisting that people should not be punished for what they believe or say. As John Locke argued in his 1689 “Letter Concerning Toleration”, no man should be attacked by “fire or sword” for what lurks in his mind.

In Europe in 2015, cartoonists and writers were punished by “fire” — gunfire — for their beliefs. And in treating this as understandable, liberals showed that they haven’t only abandoned Charlie Hebdo — they’ve abandoned the very idea of the Enlightenment, the modernity-defining freedom to doubt and disbelieve and be heretical.

They justify their caginess about offensive speech as an attempt to combat Islamophobia: they just want to make sure Muslims don’t feel unvalued or threatened. Don’t be fooled by such PC-speak. For their true concern is the one that has motored every censor in history: that the masses might be whipped into a frenzy if they’re allowed to engage with “dangerous" ideas.

Their fear that Charlie Hebdo might unleash Muslim-baiting among the populace is like Torquemada’s concern that heretical texts could turn the plebs against God, or Victorian censors’ worry that images of scantily clad women could make men rapacious. With its panic about the presumed passions of the masses, the post-Charlie call for moral self-policing is indistinguishable from the elitism and dread of the public that always underpin censorship.

The anti-Charlie elitists are having a dire impact on freedom of thought. They’re limiting what people feel they can say about Islam. They discourage eccentric thinking in favor of having us all to bend our knee at the altar of safe, PC ideas.

And their myopic obsession with Islamophobia also makes it hard to discuss anti-Semitism in Europe, as evidenced by the fact that the massacre of four Jews in a kosher deli two days after the Charlie killings rarely features in our look-back on those days. Perhaps it’s Islamophobic to talk about anti-Semitism, especially if it comes from Muslims?

The Charlie killings revealed that there are individuals who will slaughter us for what we say, and an army of pseudo-liberals who will apologize for their actions. The gunmen killed 12 people; but it’s these chattering-class moral cowards who are killing the Enlightenment.

Brendan O'Neill is editor of the online magazine spiked and a writer for the Spectator in the UK. Follow him on Twitter: @Spikedonline