Until now, we have been spared a major attack on Belgian soil. Sadly, the sickening events of 22 March abruptly changed that. Brussels now joins the growing list of European cities that have been targeted for mass casualty attacks: Madrid, London and Paris.
But this week's slaughter wasn't just an attack on Belgium. Maalbeek metro station, where so many innocent men, women and children died, is a key transit hub for the European district. We now know at least 40 different nationalities were caught up in the attacks. This was a strike at the heart of Europe.
More than ever, it's clear we are facing a European challenge. If we are to defeat those who wish to harm us, we need more than rallies and calls for solidarity; we need collective European action to improve security and deliver effective counter-radicalisation strategies across Europe.
If we are to succeed, we must first acknowledge the scale of the challenges we face and address the root causes of these attacks. What drives our young people to want to blow themselves up in our airports and metro stations?
We know that modern terrorist cells are well organised, very mobile and autonomous. They may not be under a central command, but they are all inspired by the so called Islamic State. As long as IS and their twisted ideology continue to flourish, their agents will continue to attempt to recruit and train vulnerable European youth and we will never be fully secure.
It's clear that across Europe, we must do more to exchange best practice and expertise in counter- radicalisation. We must also do much more to improve integration and tackle the poverty and unemployment which prevails in so many communities. People who have no hope of employment and little opportunity are much easier to recruit.
We must also club together to do much more to tackle the instability and conflict on Europe's doorsteps ;in Syria, Iraq and Libya. For too long, Europeans and their political leaders have failed to make progress on building a European defence capability. The assumption was always that the Americans and NATO would protect us. But while we scaled back our defence capabilities, we have discovered the US has had its own agenda. President Obama switched US priorities from the Middle East to Asia. The intervention we have seen hasn't been consistent and Europe is now paying the price. We are the recipients of an uncontrolled flow of refugees, an aggressive Russia on our doorstep and barbaric terrorist attacks, yet we do not have the means to deliver a collective response to these challenges. We must face the fact that finding a political solution to the Syrian war is a European responsibility and that only a strong European coalition can deliver a political solution to this conflict.
The other area where we urgently need to do more is to improve the coordination of anti-terrorism and intelligence gathering itself. After every recent terrorist atrocity in Europe, our leaders have admitted the exchange of information between national intelligence services could have been improved. This was very much the conclusion of the Paris attacks last year, yet when it's time to take those decisions, leaders argue that mandatory sharing goes too far.
I believe the mandatory exchange of operational intelligence is vital. In fact, I believe there should be a European intelligence service which will collect data and set up operations in all 28 Member States. Theresa May, the British Home Secretary made it clear that UK intelligence agents have been helping the Belgian services in is recent operations. This kind of cooperation should be expanded and is a vital way to raise standards and share expertise. If terrorists don't respect national borders, why should our intelligence agencies?
EU leaders have been obsessed with creating a European system for the collection of flight passenger data, called "PNR". Tragically, this proposed instrument still contains no European database, but is a collection of 28 national databases. Data is only exchanged when a country requests it and only flights are covered. PNR information is therefore of little use if we want to break up Franco-Belgian terrorist cells.
At each step, the reluctance of EU leaders to reach European solutions has been startling. It's a cliché to call it 'gross negligence', but it starts to look like that; we still have no European Border and Coast Guard, limited European intelligence cooperation and no European defence capability.
The European Union was able to adopt a European arrest warrant after 9/11 which will now be used to extradite Salah Abdeslam to France. Was this a violation of national sovereignty? To an extent it was, but every European has become safer because of it. Some sovereignty was pooled, but security has been enhanced.
The attacks in Paris and Brussels are our 9/11. It is now more important than ever to leave the rhetoric about increased coordination behind us and take real action at European level.
Guy Verhofstadt is the former Prime Minister of Belgium and leader of the Liberal and Democrat group in the European Parliament
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