One thing, however, I know with certainty: violence, or the direct threat of violence, of the kind we have seen in the past few days, is totally unjustified as a response to any published word or image.

If you had said to anyone in 1945, at the end of the Second World War with the continent it ruins, that you could have a European Union of 28 member states stretching from Portugal in the West to Estonia in the East, all of them more-or-less liberal democracies - they wouldn't have believed you.

Starting from the ruins of the Second World War, we - all Europeans said, after centuries of fighting each other, we're going to build permanent arrangements in which peace between European countries is secured, freedom is secured, and growing prosperity. And that's what we have done over the last 70 years.

People feel that European institutions are remote and bureaucratic, run by shady cosmopolitan elites. Britain is not absolutely exceptional because if you look at the opinion polls, those sentiments are now quite widespread also in continental Europe.

But transitions from the politics of violence to democratic compromise are always messy.

The whole project of European Union is one in deep trouble.

Developments in information technology and globalised media mean that the most powerful military in the history of the world can lose a war, not on the battlefield of dust and blood, but on the battlefield of world opinion.