A vigil in remembrance of the 14 people lost Wednesday in the San Bernardino mass shooting. (Tom Tingle/Associated Press)

“Mommy, what did the news used to be about before it was about terrorism?”

That was my younger daughter, snuggling in bed a few weeks after 9/11. She was then 4, and, granted, there was probably more consumption of news in our home than was healthy.

Fourteen years later, that toddler is a college freshman, too cool to snuggle and too far away even if she were so inclined. But her question remains sadly relevant.

“It’s really scary to grow up in a time when mass killings happen this often,” she texted Wednesday afternoon, as the latest active shooting situation was still unfolding.

And, knowing her mom, “Are you gonna write about it?”

What, I asked, should I say? “Maybe how when things like this happen so frequently it desensitizes people to violence,” she texted. “I was watching the news and they were showing footage from what happened today. And [my friend] just looks at the TV and goes, ‘It’s hard to be sad about stuff like this when it happens every other week.’ ”

If only the carnage were that infrequent.

Indeed, her older sister checked in Thursday morning from London, where she is concluding a semester abroad, quoting the New Yorker: “Week by week, or, recently, hour by hour, we tally the carnage.” How happy am I to have a New Yorker-reading child; how terrible that this is what she reads.

The columnist’s instinct is to examine an issue and propose solutions — if not perfect fixes, at least half-measures. And so, in response to mass shootings, I have written about tightening background checks and limiting magazine sizes; about cracking down on domestic abusers and requiring trigger locks.

Today, I find myself suggestion-free, just sad. My daughter’s friend notwithstanding, I don’t think we are desensitized by this killing. We are depressed — by its omnipresence, its persistence, its multiplicity of sources, whether right-wing extremists, disaffected high school students, or, yes, Islamist terrorists, home-grown and overseas.

And by the seeming insistence of our political system on repelling even the slightest changes in the direction of sanity. “We should never think that this is something that just happens in the ordinary course of events, because it doesn’t happen with the same frequency in other countries,” President Obama cautioned, once again. True, yet I despair of dislodging the legislative gridlock.

Every episode is terrible in its own way — innocent children at Sandy Hook, innocent movie patrons in Aurora, innocent churchgoers in Charleston. Still, something about San Bernardino feels especially disturbing and ominous.

Partly it is the rapid, seemingly incessant pileup of shootings. Another? Already? Partly, it is the bizarre mashup of workplace violence and Islamist terrorism.

The scariest part, as the story develops, involves the lethal intersection of permissive U.S. gun laws and Islamic State sympathizers — not an unprecedented event, but the deadliest yet, and a chilling reminder of that dangerous pairing.

And the creepiest part is the way in which this event falls outside the comfortable compartments into which we fit these episodes to try to make sense of the senseless.

Syed Farook was no marginalized drifter — he was a U.S. citizen with a college degree and a decent job, devout yet seemingly integrated into modern society. That he was not an obvious candidate for radicalization makes his actions all the more alarming.

As to his wife, Tashfeen Malik — we are inured to the threat of the lone wolf. The jihadi mama grizzly, willing to abandon her 6-month-old for the cause, is a more alien, more unsettling idea.

To live is to accept some measure of risk; otherwise we would not venture outside a sanitary bubble. When my daughters express anxiety about a terrorist attack, I wave it off and tell them they should fear driving on the Beltway instead.

But I find myself wondering these days: Which do I worry about more? The child at college when the National Rifle Association is lobbying to allow more weapons on campus? The one traveling overseas, from European capital to European capital? Or either one at home, driving that Beltway? The parent’s plight, of course, is to be ever aware of these hazards, and more.

My children’s consciousness of current affairs dawned on 9/11. They heard the mommies debate Anthrax precautions on the playground. They were kept indoors, soccer seasons ruined, when two snipers terrorized our region a year later.

Now they are nearly grown, too old to shield from bad news, too young to have lived through so much of it. And so the question evolves: Not what do we tell our children, but what will they be telling theirs?

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