50 years ago this week construction began on the Berlin Wall. The wall came to symbolise the rigid divisions in ideology between Western and Eastern Europe and the brutal, uncompromising authoritarianism which held sway from Rostock to Vladivostok. Churchill's term 'the Iron Curtain' found no greater expression than the wall that divided Berlin from 1961 to 1989.
The fall of the Berlin Wall ended the era of superpower politics and the crowning of Uncle Sam as the world's patriarch. But within two decades, great changes have taken hold.
The US has acknowledged it can no longer serve as the world's policeman and it needs friends fast to respond to the changes that climate change and global recession pose. Europe, the big economic and political success story of the post war era, has also hit the rocks now unable to afford cherished institutions rooted in social democracy ideals.
With the certainties of the Cold War disappearing, it has taken 20 years for many political leaders to think about how they need to engage in an uncertain multi-polar world. At the same time, rapid advances in technology have had a profound impact on communications and the way we conduct our affairs.
The complexities of this predicament seem only to grow as we reflect this week over the increased prospects of a second global recession and disturbing social unrest in London.
As a resident on a street in Hackney which witnessed appalling scenes of violence and looting, I stopped in stunned disbelief at how our community appeared so vulnerable in the face of mob anger. Clearly, there are many complicated and sustained reasons behind the social unrest which has gripped the UK over the past week.
Here in France where I write, the media has been quick to remind us of the British criticisms of the causes for, and the handling of, the riots that rocked France in 2005. They, too, were borne out of a lack of faith among a disaffected youth in a system which offered them no future. As Le Monde observed the British have been complacent over "les mérites du modèle britannique de mixité urbaine et sociale". The paper dubbed the British riots as 'Les révoltés du «no future».
Perhaps the most distressing aspect of the riots is the sense of vulnerability. Authority simply vapourised. Law abiding individuals and communities have felt the same chilling vulnerability as the most valued and respected institutions which were assaulted. Suddenly a nation which basks in its reputation as a home of social tolerance, successful multi-culturalism and even-handed law-and-order appears not to be the success story it had once supposed.
Authority and the institutions which symbolise and uphold authority have been shown to be exposed in the face of small but concerted civilian action. Equipped with technology, notably social media, the protagonists have mobilised rapidly and improvised in the field. We witnessed urban guerrilla combat which could have resulted in a great deal more debilitating damage were they in any way better organised or equipped. In the fragile ecosystem that is London, it wouldn't take much to bring the city to a halt and in the ensuing chaos create fear and panic.
The fragility of authority will be in the uppermost thoughts of politicians, the police and security specialists. The temptation in the UK as elsewhere in Europe will be to introduce greater social controls - new stop-and-search powers, new control orders, longer sentencing. In other words, introduce more measures which have helped breed the existing discontent, particularly among the dispossessed.
Striking the balance between safety and civil liberties is an ongoing challenge in all mature societies. A significant strand that unites Europe is that shared belief in the social compact; that society will look after its own and will provide for the weakest and least abled. But we are witnessing a time of increased economic hardship for the many throughout Europe, coupled with a loss of cherished privileges which form part of that social compact.
The Great Depression of 1929 lasted through much of the 1930s and ultimately led to dictatorship and war in Europe and the wider world. That war didn't end until fall of the Berlin Wall.
We are in the deepest economic difficulties since 1929 and while we are unlikely to see a return to war in Europe, there exists the same conditions for social unrest, agitation and the challenge to the institutions of authority.
The biggest task facing our political leaders is striking a balance between defending those pillars of authority while not erring towards authoritarianism.