As the dust settles from the Charlie Hebdo shootings in Paris, an ugly picture emerges. The consensus that holds society together is breaking down. We may all agree that murder is wrong, but we disagree on how to combat extremists, how to live with foreign cultures and, indeed, the scope of free speech. The cosmopolitanism that prevails amongst society's elite is challenged. And yet the only solution is to embrace cosmopolitan ideas yet further.
On the one hand we have the Islamic extremists themselves. We haven't learnt much new here. Their alienation is such that they feel at war with western (and not just western) states, and they have ceased to see their opponents as human beings. The Paris assailants drew a distinction between "civilians", whom they should not attack, and others, including journalists and Jews, whom it was OK to kill. This will no doubt aid the process of self-justification in their own circles - but the contradictions are too obvious to everybody else. The extremists appear to have momentum, especially led by the success of the Islamic State in Syria and Iraq. But their attacks, and their revelling in the power of life and death, should alienate them from the rest of society, outside the failed states in the Middle East and Africa.
We could take comfort from that if it wasn't for dark forces working within the rest of society. Foremost amongst these is the rise of nativism in Europe and America. Nativists are intensely suspicious of any foreigners in their land. As we come to the end of the era of easy economic growth, and as technology destroys swathes of stable, clerical and factory jobs, faith in the idea of progress wanes. Nativists hark back to an earlier age that seemed simpler. They blame immigration for its undermining. Islamic immigrants have become a particular focus of suspicion. Ideas of a clash of civilisations, even a war, take currency. Nativism seems particularly strong in places with small immigrant communities, such as Clacton in England or, on an altogether larger scale, Dresden in Germany. But large, unintegrated ethnic minority communities provoke similar fears in neighbouring communities too. This accounts for the rise of perhaps the most important nativist movement: the National Front in France.
In Britain the rise of nativism is led by Ukip. Originally Ukip focused on Britain's membership of the European Union, but it struck electoral gold when it shifted to opposition to immigration. The mainstream Conservative and Labour parties started to panic as Ukip ate into their core support, giving nativism further impetus. Tabloid newspapers stirred things up. As a result public attitudes to ethnic minorities have soured in much of the country. The idea of "freedom of speech" is now used to defend the open expression of Islamophobic views - though the idea that such freedoms should extend to the expression of Islamist or anti-Semitic views is not aired. The outcry of the Charlie Hebdo killings has given such nativists and their prejudices a real fillip.
Which makes matters worse. The entire Islamic community finds itself under attack. People say that all Muslims are to blame for extremists, and should apologise for them. Now the Muslim communities must face up to some important questions about how they are to progress and integrate into a modern world - questions that many are reluctant to confront. But ignorant prejudice serves only to alienate them, and prolong the sense of grievance on which the extremists feed.
And so we face the prospect of an unravelling. Globalisation is integral to the western way of life. Just think of the rise of the British Empire and the cities that have been built on the back of the African slave trade in the 18th Century if you think it is anything recent. Large immigrant communities are simply a continuation of that process, in an actually much more benign way. Denying globalisation is as futile as Britons denying that their country is European. Nativism is a road to nowhere, or rather a road to poverty and conflict.
Instead we must embrace the values of cosmopolitanism. These are articulated most clearly by the Ghanaian-born author Kwame Anthony Appiah (as in Cosmopolitanism - Ethics in a world of Strangers). We must accept that our culture is the product of many cultures melding together in a process that has being going on for millennia, and which is destined to continue. There is no such thing as cultural purity, and no point in trying to defend it. This is not the same as relativism, which backs away from defining any kind of right or wrong ethical values. It means embracing ethical values which accept that all the globe's inhabitants are part of an "us", even though we recognise stronger affinities with some rather than others. People of different cultures should enter conversations with each other, and accept that their outlooks may change as a result.
Cosmopolitanism has always been embraced by elites, especially in the west after the nightmare of Fascism, which showed the futility of its opposite. That accounts for the many cosmopolitan aspects of our institutions. But now it is vital that it is taken up by all of society: amongst working class communities and ethnic minorities too. Here in London, perhaps, this process is quite well advanced, though hardly complete (I'm afraid that Islamophobic attitudes remain commonplace). Different communities are forced to mingle. We go to school together; we work together; increasingly we have children together. Elsewhere, though, we have just taken a backward step.
But I remain hopeful. The young are more cosmopolitan than their elders. Our cultural and business leaders, by and large, remain firm. At a time when elites are under attack for being out of touch, it is time for them do what elites should: to show leadership.