On this side of the House, we support everything the Home Secretary has said today and assure her of our continued full support in confronting this threat.
Today our thoughts are with the families of those killed or injured, the British person who is missing and with the people of Brussels.
We think of all the people who have suffered in the attacks the Home Secretary has mentioned, including the recent attacks in Istanbul and Ankara.
But Mr Speaker, this was more than an attack on Belgium.
It was an attack on the heart of Europe and on all of Europe.
A statement of intent from the terrorists which must now be met with a raised and renewed determination to defeat them.
Let me start with immediate advice to UK citizens.
We welcome the support being provided to those caught up in the chaos.
But as we approach Easter, many families may have travel plans that include travelling to or through Belgium.
Will the Government consider issuing more detailed travel guidance to them so people can make decisions based on the best available information?
Second, let me turn to international collaboration.
Can she say more about the nature of the immediate support that has been provided to Belgium?
People will have seen reports suggesting that the suspects were linked to the attacks in Paris and known to Belgian Police.
This does raise the question of whether the Belgian authorities have sufficient capability to deal with the extent of this problem.
Is there more that can be done to support them on a longer-term basis?
More broadly, can I say that given the global nature of this threat, she is entirely right to talk about deepening our collaboration with all European partners?
Third, Mr Speaker, let me turn to border security.
We are learning more about the extent of terror networks in Belgium.
And, as we do, this raises questions about travel between the UK and Belgium.
Britain has extensive air, sea and rail borders with Belgium.
We welcome the immediate steps taken yesterday to strengthen the presence at our borders with Belgium, but is there now a case for a longer-term review?
Border Force operates juxtaposed controls at six locations in France. However, in respect of Belgium, juxtaposed controls apply only in respect of Eurostar and not at ferry terminals.
Will the Home Secretary immediately initiate a review of our borders with Belgium with a view to strengthening them?
She knows of the concerns I have raised before about UK terror suspects on police bail who have fled the country.
We are proposing an amendment to the Policing and Crime Bill to close this loophole.
Will she today give a commitment to work with us on that?
More broadly on borders, Mr Speaker, I have serious concerns about the further cuts that are coming following the spending review.
The Border Force has faced years of cuts and is already stretched to the limit.
The new financial year starts in a week's time but I notice that the Home Office is still to publish a 2016/17 budget for the Border Force.
Will the Home Secretary correct that today so that there can be a debate about whether it is enough and whether further border cuts are wise in the wake of Paris and Brussels?
Surely now is the time to strengthen our borders, not cut them?
Fourthly, Mr Speaker, let me turn to UK preparedness.
We know that seven terror plots have been foiled here in the last 12 months and we thank all those in the police and security services who are working to keep us safe.
But we must keep our own arrangements under review.
The public will want reassurance about our ability to cope with a Paris or Brussels style attack - multiple, simultaneous incidents designed to cause maximum fear and confusion.
We know plans are in hand to improve firearms capability in London, and we welcome those, but there is a concern about the ability of cities outside London to cope, given cuts to police and fire services.
A Home Office report on Police firearms capability - published in July 2015 - found the number of armed officers had fallen by 15 per cent since 2008, from nearly 7,000 to 5,875, including a 27% fall in Greater Manchester and 25% in Merseyside.
There was a report in the Observer late last year that Scotland Yard has briefed the Home Secretary about their fears of the lack of capacity in regional forces to respond to terror attacks.
Is this true and can she say more about it?
Has she reviewed the ability of all major cities to respond and can she provide reassurance today that if there were to be a Paris- or Brussels-style attack outside of London that our police and fire services have the necessary capability to respond?
In conclusion, Mr Speaker.
While we think of the Belgian people today, we also think those harmed by last week's attacks on Ankara and Istanbul.
We remember today that many victims of attacks around the world are Muslims, suggesting this terror is not about Islam.
We also know that, at moments like this, great anxiety will be felt in the British Muslim community, with fears of reprisal attacks, rising Islamophobia and hate crime.
Does she recognise that concern and will she today send an unequivocal message that anyone who seeks to promote division or hate on the back of these attacks will be dealt with severely?
Will she condemn the ill-informed comments on UK television today from Donald Trump and take this opportunity to distance the UK government from them?
They play into the hands of the terrorists.
They want to drive a wedge between the Muslim community and society – who in fact are united in revulsion at what happened yesterday.
Da'esh called the innocent people who died and were injured crusaders. They are nothing of the sort. They were ordinary, innocent people of all faiths and none, living side by side in one of Europe's great cities.
This is the moment for maximum unity amongst peoples of all faiths and none.
A moment to reject those who preach Islamophobia, anti-semitism and all forms of extremism.
Let this unanimous message go from this House today: that we stand together across it as a united country; that we stand with our neighbour Belgium in their hour of need; and that whatever it takes, and however long it takes, we will face and defeat this threat to our way of life together.