Brussels is the most international city in the EU. It's the heart of Europe. It welcomes people from every part of the world as international politics and business play out on a daily basis. Thousands of Irish people live here, working in the public and private sectors. It's a place where students hang out and genuinely feel a common European identity.
Yesterday's attacks have unnerved and undermined the natural confidence of this city as a place where deals are made - and hope, just sometimes, can be restored.
Europe's capital was rocked to its core yesterday as innocent people lost their lives to terrorism.
Given the pre-Christmas terror alert and the arrest last week of Europe's most wanted man, Salah Abdeslam, there was an expectation that something terrible could happen. But that threat did not deter people from getting on with their lives. Yes, people were conscience of the security, seeing the army on the streets, but nothing prepares you for an unprovoked attack in the civilian population.
It's virtually impossible to stop a lone suicide attacker from detonating a bomb. The metro station at Maelbeek and the airport in Brussels were the easiest of all targets for the terrorists. A crowded place where people gather, as they try to catch a train or airplane, is such an everyday occurrence in this city as people move about.
As someone who travels through Brussels airport every week on my way to Dublin, sometimes twice a week, it's unimaginable to consider the panic that ensued yesterday. For those of us who use the airport so frequently - it's a bit like a big bus station. Our journeys to and from the airport are planned to maximise time. The departure area, where the shooting and bombing occurred, is part of our weekly travel routine.
It takes just 80 minutes' flying time between Dublin and Brussels. Every day six flights go from Dublin to Brussels and visa-versa. Thousands of Irish people are in the airport every day. You regularly bump into people you know. Yesterday those flights from Dublin were diverted to Amsterdam as Brussels airport became a no-go area.
Maelbeek Metro station is a stone's throw from where I work. It's next to the EU Parliament, and is one stop away from the EU Commission and the EU Council. The detonation of that second bomb on the Metro line sent a clear message to all EU citizens. The metro became a place of carnage, death and injury.
Innocent people going about their daily lives represent the new frontline for extremists. Innocent people murdered and injured because they want and believe in a Europe at peace.
In the EU Parliament yesterday, everyone was shocked by the brutality of these latest attacks. As colleagues enquired about the safety of staff and loved ones, there was also a defiance that those responsible cannot destroy the progress that Europe has made.
Freedom of movement and the opening of borders represents the greatest success of the EU. Young people traveling and working across the EU is a demonstration of EU rights and freedoms. Yesterday's attacks in Brussels, as in Paris last year or in Madrid and London previously, cannot be allowed to create a 'fortress Europe'.
We must be supportive of the security decisions that are in place or to come. But we must also support the basic freedoms that all Europeans enjoy. In doing that we can defeat those that offer nothing but death and a new war between civilisations.
As an Irish person who is privileged to represent my country here in the EU Parliament - we must all stand with Belgium and with the EU.
Brian Hayes is a Fine Gael MEP