It is a natural human response to look into the smoky aftermath of tragedy hoping to glimpse a larger meaning, some lesson that the living might learn. That meaning is all the harder to discern when the victims are children, either taken at the start of their lives or shackled for the remainder of them with scars that never fully heal.

On Monday evening at an Ariana Grande concert in the northern England city of Manchester, a 22-year-old British-born man identified by police as the bomber killed 22 people and wounded at least 59 others. Many were young. It was a split-second detonation that will long linger in the lives of those who survived it and in the city where it took place. The most insidious thing about trauma is that it is transmissible in communities where it persists.

This week’s attack was the deadliest terror strike in Great Britain since 2005, when Islamic militants there killed 52 people and wounded more than 700 in coordinated explosions on London’s transit system. It was the biggest terrorist attack in Manchester since June 1996, when a Provisional Irish Republican Army truck bomb wounded more than 200. Decades later, Mancunians still remember that attack, and many haven’t forgiven its perpetrators.

Attacks targeting civilians are often the last refuge of scoundrels — “losers’’ as both Donald Trump and Ruslan Tsarni, uncle of the Boston Marathon bombers, would call them — who can’t lure converts to their causes without the bait of innocent bloodshed. The Islamic State group — as eager for carnage as they are for publicity — claimed responsibility for the Manchester attack.

Subsequent investigations will surely uncover more about those responsible. But the police say the bomber lived only a few miles from the site of his massacre. And so Manchester joins a growing list of cities attacked not by outsiders, but by people living in their own communities: Boston, Paris, Nice, and Brussels, to name a few. The most terrifying thing about homegrown extremism is that violent ideas — no matter how antithetical they may be to a free society — can still find fertile ground to grow in the minds of neighbors.

Perhaps that’s the only lesson — one the British have long known — that even though a bomber may always get through, a vital defense against evil is a resilient community, capable of withstanding the nihilism of terrorist violence, whatever its ideology. A society that keeps calm and carries on.