H.A. Hellyer, senior nonresident fellow at the Atlantic Council and the Royal United Services Institute in London, is author of "Muslims of Europe: The 'Other' Europeans" and "A Revolution Undone: Egypt's Road Beyond Revolt." He is on Twitter @hahellyer . The opinions in this article belong to the author.

As I woke up to the news from Mancheste r, that was my immediate reaction. I'm not from the north -- my family hails from Sussex in the south of England. But as a young man at university (not that much older than many of last night's concertgoers), I lived in Sheffield, some 40 miles away from Manchester, for four years.

As the days go on, we will learn the identities of all those who died in this atrocity -- and one thing is certain to stand out. The ages of those who perished will linger -- because disproportionately, the targets of this horrific attack were children and teenagers. But as hard as it is, we must keep our heads -- because panic is what the perpetrators of this horrific event want from us.

This is the largest terrorist atrocity on British soil since the 7th of July bombings in 2005 -- but only on British soil. Vicious violence by criminals and radical extremists has taken the lives of many in Europe in far greater numbers --and even more, when we consider the carnages that unfold on a daily basis in parts of the Arab world at the hands of brutal autocrats like the Assad regime, or radical extremists like ISIS and their ilk.

And the Manchester attack isn't unique for targeting young people, either. In 2011, white supremacist and Islamophobe Anders Breivik killed 77 people in Norway -- many of them, if not most of them, were teenagers. But our memories are too short. In our current state of righteous outrage, we must also be precise to avoid another terrorist trap.

We will be called upon to react -- and react we should. But the reaction ought not to be some kind of new "state of emergency" that some have called for , or other kinds of knee-jerk alarmism. That's patently what the attacker would have wanted -- it's what terrorists always want. It's a victory we should never grant them. Manchester is resilient, and it will persevere, survive and thrive -- and that's the real message of this tragedy.

When I heard a Fox News commentator declare that Manchester was a "hotbed" of radical extremism, it was as if he were describing a different city entirely from the one we saw in the aftermath of the attack. The attackers didn't represent Manchester -- the locals of all ages, creeds and colors who worked together as ordinary citizens, the police officers and first responders who tended to those caught up in the horrific consequences: they are Manchester.

ISIS has claimed the attack , but of course, ISIS has an interest in projecting its power beyond its actual means -- so its statements ought to be taken with a bucket of salt.

The fact of the matter is, we can expect more attacks of this nature to be attempted -- and many more have already been attempted, while foiled by our security services. That is the world in which we, and many others around the world, now live.

But it is our collective choice as to how we live in that world. It isn't a choice between security and insecurity -- security measures that are necessary are in place. It's a choice between allowing terrorists to win in changing our ways of life, and refusing them that success. When a columnist (in a terribly ill-considered and now-deleted tweet, for example ) calls for a "final solution," they've made a choice -- it's a choice that uses the language of ethnic cleansing and genocide.

Lesser statements in that same paltry direction insist that Muslims should "do more" to fight extremism -- ignoring that Muslim Britons themselves were also attacked on Monday night. They're not responsible for an outrage they had nothing to do with, any more than all white people baptized in Protestant churches had anything to do with Breivik's murderous rampage in Norway.

And, yet, as the news came in of the attack, spontaneously, a Muslim scholar I know sent me a message. It was short, but to the point, and ended with this particular verse from the Quran

"O you who believe! Be maintainers of justice, bearers of witness for God's sake, though it may be against your own selves or (your) parents or near relatives."

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It's a message that all of us can take wisdom from, because this latest attack, and the baser temptations we face in its aftermath, is about rejecting justice. It's the easier thing to do -- but it is precisely that deception we must see through.

One day, ISIS will be remembered only as the failed cult that it is, like so many other horrors that came before it -- and we should ensure that our children can remember that ISIS failed utterly in every way -- including their efforts to steal our humanity. That's our choice to make.