When it emerged that bloodthirsty men were shooting people at the Paris offices of the satirical weekly Charlie Hebdo last year, Irish novelist Robert Wilson was at home across the city, glued to Twitter.
He wasn't a witness, but he knew, perhaps better than others, what was happening.
"As someone brought up in Belfast, I could tell very quickly it was going to be grim, and the toll would mount, and because it was guns, the ratio of dead to injured would be very high," he said.
He was right, of course. This is a man who lived through decades of bombings and assassinations in Northern Ireland. His novel Eureka Street about that wrenching world became a BBC television series. It is funny and gloomy and whiplash fast and just ever so slightly sketchy.
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That's pretty much Robert Wilson, too. And it's possible he'd simply nod at that description and light another hand-rolled cigarette.
He knows a thing or two about the effects of terrorism or political violence, whatever label you give it.
"If this goes on, it really changes your DNA: it changes who you are," he said. "Terrorism or political violence isn't about the victim. It's about the rest of us. It is about changing the way a city or country operates."
Northern Ireland's "troubles" certainly changed him. But so did Paris of 2015. He was hired by Charlie Hebdo in the weeks after the attack. It sadly needed staff, and he didn't hesitate to stand with them.
He was a newcomer at the paper and is still a foreigner in Paris, but people turn to him for advice on how to cope with all of this.
"And the problem is I couldn't remember what it felt like to go through this for the first time, because I was a very small child, and the only thing I remember is that it wasn't my fault," he said.
His only advice was to do nothing, because he believes nothing any one person can do will make a whit of difference. Terrorism is a "minority sport" where the very few bully an entire nation to shift.
And some of those shifts are about human impulses. It's about what happens when people subconsciously count the ambulances they hear as they walk along the street.
One? Maybe someone's had a heart attack. Two? That's probably a car accident. Three? Oh no.
The shift is still subtle in Paris, but it's real. Since the Nov. 13 attacks, several chain stores that typically hire all-seeing security guards to keep watch for shoplifters have moved guards to entrances.
It's whatever you may be bringing into the store that's the worry now, not necessarily whether you've nicked a stick of deodorant.
Day by day, Parisians are getting used to it.
People who live in, say, Jerusalem, tell stories of going on vacation to some European capital and reflexively wandering into a store, with bag wide open, arms stretched out for a security search that never comes.
Inevitably, the tale includes weird glances from other shoppers, a raised eyebrow from the guard and a few embarrassed chuckles about old ugly habits being hard to kick.
Beautiful Paris has been the city where you are supposed to be able to shake those usually corrosive thoughts.
But "Generation Bataclan" may sadly be learning these impulses. That the young, dewy-eyed Parisians who lost so many of their own in November's slaughter are still so horrified and stricken seems to comfort Wilson.
Watching them cling to each other on the metro in the days after — "like kittens," he says — reminded him they are, mercifully, not yet him.
"Their innocence and their surprise is deeply human. You should be surprised by this stuff," he said.
"It was the candles that did it for me. They were so lovely and so sweet. They were so clumsy and so human. They're pointless, and they are not going to persuade any psychopathic fascist arsehole from not doing what he intends to do. It was about beautiful futility."
How do you know when that innocence is lost?
"I'm not sure it has been yet," he said.
"I think if a bomb went off here right now, people wouldn't do what we did then … 'Do you think it was Bedford Street or Jumna Street?' … They would still be shocked.
"It's the moment you treat it like a traffic jam that it's lost. I don't want them to end up like me — so blasé, so accustomed."
Just before the November attacks he recognized something happening with his new Charlie Hebdo colleagues. It's what he refers to as the "six-month mark".
It's something that people from places that have endured outrageous violence know all about, Wilson said.
"You can struggle on and deal with it, and six months on you fall apart. Your life is a wreck. You function well, you've gone back to work, you have looked after your family and you become a wreck…. It kind of started happening at Charlie. Some people left, some people backed away a bit."
Wilson adores his new colleagues and has a protective tenderness toward them, but it is public knowledge that the Charlie Hebdo staff have been struggling.
There's been infighting about how the once-marginal, poor paper will manage the flow of money that came in after the attacks. There are conflicts over editorial direction, too.
Terrorism changes people. And it has definitely changed Charlie Hebdo. Wilson's hope is that he doesn't start recognizing more of those changes in Paris — that bloodshed continues to be hideous shock, and not just another bad day.