Manchester terror: Rise of suicide bombing makes police job harder
Almost a decade and a half ago I co-produced a documentary series on the history of paramilitary bombings during the Troubles.
It allowed me to pose a question that has nagged away at me for years when covering conflicts in Northern Ireland and the Middle East.
Finally I got to ask one of the men who blew up large areas of Belfast from the 1970s this: why, despite a history of hunger striking, from Terence MacSwiney to Bobby Sands, did any strand of Irish republicanism never produce a suicide bomber?
This conundrum had puzzled me long before 9/11.
I had encountered families of suicide bombers long before that world-changing day in southern Lebanon, and watched their videos of sons and brothers immolating themselves in explosions at Israeli army checkpoints.
And while in the Shia Muslim redoubts of south Lebanon, my mind often turned to home, to the question of why the cult of martyrdom and death running through republican history did not produce the Irish suicide bomber.
When I finally got to pose that question, the Provisional IRA's one time 'Engineering Officer' in Belfast looked at me as if I wasn't wise. With brutal frankness he said any recruit who volunteered to blow themselves up at an Army or RUC checkpoint would be sent packing, probably to the nearest psychiatric care centre.
Pressed on why his comrades had starved themselves to death in the Maze while the organisation refused to countenance the suicide bomb, the IRA man made a simple point: "In the hunger strike there was always, right close to the end, a back door to life again. But once you push the button on a suicide belt then it's over."
Bombs, especially homemade ones, have a habit of being highly unstable, unpredictable and indiscriminate weapons of war. In the Troubles they were used with criminal disregard for civilian life, from the slaughter in Dublin in 1974, to Bloody Friday in Belfast and Omagh in 1998.
Even in the era before the suicide bomber, explosive devices posed nightmarish challenges for police trying to clear the danger zones.
Inadequate or inaccurate warnings led to mass casualties during the Troubles, such as at Omagh, where the bombers cynically tried to catch the police in the blast as they evacuated the centre of the town.
Now try to imagine you are a police officer having to cope with something even more lethal and deadly in the 21st century - the no-warning, self-immolating bomber who thinks he will ascend to paradise after the blast.
There has been some criticism levelled at Manchester police for allegedly failing to clear the area around the concert that led to so much terrible carnage on Monday night.
For those of us who lived and survived the Troubles here, this charge against the Manchester officers is wholly unjustified.
They faced as their colleagues do - not only all over Britain but across the world - an opponent who, unlike the IRA or UVF, knows no boundaries when it comes to inflicting mass casualties.
It was hard enough for police forces on both sides of the border to clear areas where bombs were hidden, even with coded warnings, in the tragic years between 1969 and 1997.
It is infinitely harder now to counter the threat of an even more determined, fanatical enemy in this century.