Mal Fletcher comments on the need for restraint in any response made.

Mal Fletcher

Tunisia, Paris and, this morning, Brussels. There can be no doubt that Europe and Europeans are now the objects of consistent threats from terror cells.

Even last year's suicide bombing in Istanbul was reportedly motivated in part by the city's cosmopolitan flavour and by Turkey's desire for membership of the EU.

At the time of writing, at least 13 people have been killed and 35 have been injured in this morning's attacks in the Belgian capital. Two airports and the city's Maalbeek metro station were the target of apparent suicide bombings.

At the time of writing, estimates as to casualties are still fluid, but a clearly shaken Belgian Prime Minister has said, "What we feared has happened. We were hit by blind attacks."

Across Belgium, security levels have been raised to their highest level.

Brussels is normally a calm, clean and orderly city. Sadly, being at the heart of many of the EU's institutions has made it, for disparate terror groups, a symbol of all that is deplorable about European freedoms.

The recent capture in the city of one of last year's Paris attackers has also placed it in the spotlight. Police have said that he was planning a Brussels attack when he was caught

Two things are clear in the immediate wake of the latest carnage. The first is that national European governments and their security services must exercise restraint - as they arguably often do.

In choosing how to respond, cool heads must prevail in emergency planning groups such as Britain's COBRA. It would serve no useful purpose to base responses primarily on the understandably raw human emotion often depicted in live media reports.

The fact is that no European country is under imminent existential threat from these attacks, or those that preceded them.

No foreign army represents a credible and sustained risk to the very existence of Europe's foundational institutions, or its ability to function as an ordered society.

Though ISIS, for one, would like nothing more than to achieve those goals, it does not have either the organisation or the firepower to do so. Indeed, current reports emanating from near its previous strongholds in Syria and Iraq suggest that it is too preoccupied with its own survival there to launch any credible large-scale action elsewhere.

Without downplaying the tragedy and pain of the human loss in Brussels this morning, an over-reaction by governments would not represent a healthy response.

Doubtless, security measures around major public traffic points, such as larger stations and airports, will be scrutinised again in coming days and weeks. However, over-bearing methods would only heighten public tension, frustration and anxiety.

This in turn would make the jobs of security officers more difficult, as they can only protect the public with the public's goodwill and willing cooperation. If that implicit contract of trust were to break down, terrorists would have wreaked an even greater and more lasting level of havoc.

A measured increase in security personnel on the ground may be the right approach, but authorities will also need to look at maximising the use of new technologies.

The emergence of big data analytics, powered by cloud-based super-computers, has meant that patterns of destructive behaviour within human networks can often be identified before they breed action.

Meanwhile, increasingly sophisticated biometric readers, of the type now built into "social robots", might also be employed to highlight potentially suicidal figures within a crowd.

Here again, however, any overreaction would only breed tensions. Security forces face an unenviable task of walking the tenuous line between the demands of surveillance and the ethics of privacy.

We must also keep in mind that no amount of technology will ever rule out the truly wildcard event, which is low in probability but high in impact. Our growing digital engagement can fool us into thinking that technology gives us more control over life's twists and turns than is actually the case.

Today's events in Brussels also remind us of the failure of political correctness as either a way of thinking or a government policy.

Without for a moment diminishing the responsibility of mass murderers in Brussels, Paris and elsewhere, I think it's time we acknowledged that the political correctness of the 1990s and early 2000s has failed us. It attempted only to paper over what many commentators had foreseen were vast cultural gaps within diverse cultures.

One could take this line of thinking too far, of course. I am not arguing that we have brought these attacks upon ourselves, or that tolerance ought not to be our goal in an increasingly globalised and multicultural age.

My point is that tolerance should not mean that we abandon or apologise for our heritage and core values.

A society in which nearly everything is considered normal is self-evidently a society without norms, which are an important part of what makes us strong - and, yes, attractive to outsiders.

The debates about mass immigration - as distinct from normal immigration - should not be centred only upon whether, by allowing more people in, we can sustain public services. These are important issues, but our concerns should centre more on how well we think we can integrate people into our more effective core values - and how we measure that integration, without becoming petty or spiteful.

Finally, we should sincerely hope that tragedies like those in Brussels will not become a major feature of this country's debate about EU membership. National security arguments can be made for either side in that discussion.

Events in Belgium today are about the loss of and cruel injury to human life, not political sovereignty.