The news agenda has moved on from the awful events of 7- 9 January but, after all the agonising and argument, the dilemmas it posed for democratic societies remain unresolved.
The debate about the balance between the freedom to express opinions and the rights of those offended by them is by no means a new one. But though it's intensified since the attacks in Paris, it's doubtful that we're any closer to knowing whether and where the line can be drawn.
Blurred Lines
Few argue that freedom of speech should be absolute. The libertarian Spiked Online goes a long way in a Freedom manifesto! which proclaims that "freedom of speech must never be restricted. No state bans, no hate-speech legislation, no libel laws, no restrictions on the press, no mob pressure on people to conform to modern orthodoxies."
But Spiked's deputy editor Tim Black wrote recently that "incredible as it might seem, it is possible to defend free speech absolutely without defending perjury or incitement to murder (clue: these are not issues of free speech)".
At the other extreme, growing numbers believe that we should be protected from almost all offence. Justifying Birmingham University's Guild of Students' decision to ban the misogynist pop song 'Blurred Lines', now-deputy chair Daisy Lindlar claimed in the Huffington Post, "it is not 'censorship', as it is not an attempt to hide anything. It is an attempt to protect students from any unnecessary stress when, frankly, many of them have already been through enough".
So those who argue for absolutism believe that perjury and incitement are not actually free speech issues and those who wish to protect us from offence believe that banning pop songs is not censorship. The lines remain blurred.
Harm and Offence
Perhaps the greatest influence on our thinking about free expression remains John Stuart Mill's essay On Liberty in which he argued 150 years ago that "the only purpose for which power can be rightfully exercised over any member of a civilised community, against his will, is to prevent harm to others." He not only championed our right to speak our minds but, critically, he believed that exposure to ideas we might find offensive actually benefits us. As he contended, we cannot be confident in the strength of own opinions unless we are prepared to measure them against those of others.
So while Mill did not object to laws which protect citizens from harm, he would have rejected the idea that we should be cocooned against offence or distress. He would have warned too against a reaction to dramatic events which results in laws which ultimately undermine the freedoms they seek to defend.
Ironically, it is precisely the difficulties democratic societies face and the care they take in attempting to reconcile competing freedoms that made a satirical magazine such an obvious target for those for whom there are no such balances to strike.
Totalitarian belief systems, religious or ideological, can only fear and despise those freedoms. In societies governed by an unwavering belief in a single, unchallengeable truth, what possible virtue can there be in rights which can only benefit heretics, apostates and dissidents?
In that context, the attack by militant believers on an organ of anarchy was not just vengeance on blasphemy but also very deliberately an assault on notions of plurality in general and freedom of thought in particular.
No rational argument can justify that attack and of course the actions of a few fanatics should not be allowed to circumscribe our liberties. But neither should our sense of outrage blind us to the consequences which the thoughtless exercise or deliberate abuse of our freedoms can have for others: the right to free expression does not confer a licence to offend.
A Question of Civility
Few free speech defenders question Charlie Hebdo's right to offend. But some have questioned its purpose. While underlining the importance of satire and warning against censorship, David Brooks also observed in his New York Times column that "when you are 13, it seems daring and provocative to...stick a finger in the eye of authority, to ridicule other people's religious beliefs. But after a while that seems puerile... Most of us do try to show a modicum of respect for people of different creeds and faiths. We do try to open conversations with listening rather than insult."
Whatever one's view of Charlie Hebdo, he's surely right on both counts. We do not want to live in a world in which we are not free to think, speak and act according to our consciences. But should not our consciences also guide us in what we say and how we say it, whether in print or in the twittersphere, whether about world religions or each other? That we are legally entitled to cause offence does not make it right for us to do so in all circumstances.
We don't need new laws. We should not need politicians or judges to tell us what's offensive, even if there were some scientific means of measurement. It is we, citizens, who should be exercising judgement in the matter of both giving and taking offence - and in either case, if we are to defend our own rights, we must acknowledge those of others.
Accepting that we have equal rights to opinions does not imply that I must regard yours as valid as mine, or valid at all. Nor does it mean that I cannot offend you, simply that I should be doing so for a purpose which justifies the offence. Sometimes it's necessary to tell a friend a hard truth. But if I continue to tell hard truths for no good reason, I may lose that friend and even make an enemy. We should perhaps apply the rules of our relations with friends to those with strangers.
We may be offended by words but we are not directly harmed by them. If we find the opinions of others repugnant we should ignore, contest or, yes, ridicule them. The competition between ideas and the debates they stimulate are now as always our best hope of enlightenment and progress. We are both the staunchest guardians and the fairest regulators of free expression when we exercise it often but with civility. The line is neither in the black nor the white zone, but always somewhere in the shades of grey between. That is why it is so difficult to locate.
Ultimately that may be both the benefit and the burden of free speech - that as earnestly as we seek them, there are no certainties.