By strange and unhappy coincidence, I was going to write this week about terrorism, writes MP for Ipswich, Ben Gummer in the wake of the Westminster attacks.

I grew up far more conscious of terror than any of us would wish a child to be. My mother and father were in the Brighton Bomb and it was only by a stroke of remarkable good fortune that both of them survived: friends just feet away did not.

Staying with my aunt, aged six, I was conscious that something had happened but I was kept well away from the news and it was only years later that I became aware of just how close our family had been to something awful.

There were terrible moments in those times; many of you will remember them well. You would go for months, sometimes over a year, without an outrage, and then the news would come and the pictures and the deaths and the grieving.

It moved into all of our lives – litter bins removed from the streets of London was something all of us could see, but for our family and for others it was the daily check under the car, the security and, at times, the police at home.

My parents were wonderful in keeping it from us all but we knew enough, and at times it was very frightening.

The reason why I was going to reflect on that was because of the death of Martin McGuinness, who was at the top of the IRA through that whole period. A few months ago I met him, at the Joint Ministerial Committee, which I attend.

He sat opposite me round the cabinet table. It was a very odd feeling, to be honest, to be there – with all the resonances and ironies that that moment brought. It is a sensation felt a hundred times more keenly I am sure by those in Northern Ireland whose experience was all the more direct than my own.

I turn these articles over in my head through the week, before I commit fingers to keyboard hard up against a deadline that the Ipswich Star and East Anglian Daily Times are generous in flexing.

So it was on Wednesday, as I considered what I would say about McGuinness – and one reflection led me through what happened later that day.

The fact is that we had a near-three decade long terror campaign in Northern Ireland and mainland Great Britain – one that was ultimately defeated by our police, our army, our intelligence services and by our resilience as a nation.

It was when the men of violence had nowhere else to turn that they settled on peace. Simply put, terrorism showed itself to be futile; peace to be fruitful.

And so it will be with the terrorism that we must face today. It is as barbaric and depraved as any terrorist cult.

They wish to kill the way we live and destroy the institutions that guarantee our freedom, our liberties, our values and our prosperity.

One man gave his life on Wednesday to defend one of those institutions, others having been killed as the maniac made his murderous way to parliament. Just as before, we – and that means you and me – the civilized, free and democratic British people – will win; the deranged and barbarous terrorists will lose.

The stronger we are now, not just in the hard facts of security but in the way we conduct ourselves as leaders and communities, the more rapid and more total that victory will be.

Like my father and mother, I now have seen things that I wish I had not seen. It was with particular gratitude that I returned home on Wednesday night to Sarah and our two boys. That we all can do that in our country is because of our determination to defend our freedoms, a determination that has meant that one man was not able to do the same on Wednesday night.

These liberties are worth defending but they sometimes come at a cost. That cost is borne by brave people who work to defend us and the principles that keep our country free. Together we must win and together we will.