I lived for many years within a walk of Westminster, and still today often enter both Houses of Parliament — Lords and Commons — for meetings and events.

So yesterday’s attack didn’t require much imaginative re-creation. The idea that a knife-wielding fanatic could get right into New Palace Yard, a mere ten yards from the entrance to the Palace of Westminster itself, is terrifying to contemplate.

If it weren’t for Police Officer Keith Palmer, mourned today by his wife and children, who gave his life to stop him, it might have been much worse. And on Westminster Bridge just earlier, it was.

There, 52-year-old Khalid Masood turned his Hyundai i40 SUV into a weapon, mowing down pedestrians, crushing them under his wheels and knocking others into the Thames below. 

Three of those he hit are dead, among them a Spanish-born mother of two whose children attend a Catholic primary school.

More now suffering from “catastrophic” injuries will surely be declared dead in the coming days, and many will be maimed for life — victims of a heart and mind shriveled by the illusion of purity and power that fundamentalist religion peddles.  

But there are sparks of light in the dark cloud that dropped on London yesterday. One is that the crudeness and lone-wolf nature of the attack shows again that Daesh (Islamic State) is far less established in the UK than, say, in France.

Our James Bonds have foiled a dozen major plots in the last few years, leaving only this kind of homemade assault — one man, acting alone, with a knife and car — available to the militants.

Another is London’s long experience with terrorism. I grew up with buses and offices exploding from Irish republican grievances — there was usually a warning call, triggering panic; for the terrorists, the more mayhem, the better — and I was working for the Archbishop of Westminster in July 2005 when the worst recent terrorist assault on London took place.

As with yesterday’s attack, the militants were British-born, radicalized through hate preachers on the internet. Closing our borders wouldn’t have made any difference — but that won’t stop the nativists using yesterday to claim otherwise.

The evil in 2005 called forth from the citizens of the capital a remarkable outpouring of goodness: of forgiveness, of unity, of conversions to the cause of peace-building, of courageous victims  — many of whom came to see the cardinal, who walked with them — who became exemplars of service to others.

I learned a lot in those months about evil not having the last word, and I’ve no doubt that among the families of the maimed and slaughtered yesterday we will soon find other lessons. Already the stories are pouring in. 

The current Archbishop of Westminster, Cardinal Vincent Nichols, has called for prayer, compassionate solidarity, and calm, reminding us that God is the Father of every person. That is the best answer to the temptation of religiously-inspired terror.

The diabolical Daesh narrative  — that God is at war on behalf of the pure and righteous against ‘unbelievers’ who are condemned to die  — is easily refuted in such testimonies, and by what we call the ‘spirit of London,’ the English cousin of the New York spirit after 9/11.

Call it a determination to stand as one in our differences, against the temptation to divide. Call it by today’s hashtags: #LONDONISOPEN #WEARENOTAFRAID and so on. It works.

I remember being with Cardinal Cormac Murphy-O’Connor and other religious leaders in Trafalgar Square in 2005 as one after another they expressed their oneness with each other and the city, and their rejection of extremism and violence. It was defiant, and it was peaceful. It was, and is, victorious.

The same has happened since yesterday, in the outpouring of love and solidarity, in the quiet determination of our people to carry on. London has a fine mayor in Sadiq Khan, a Muslim who in his words and actions defies everything Daesh stands for.

When he said recently that terrorist attacks are part of life in London, he was right. They are. That’s not complacency, but realism; and realism is always a mark of strength.

To flee into an illusion of invulnerability through travel bans and crusade rhetoric is to concede far too much to Daesh. God conquered the Devil not by playing his game of power and rivalry, but unmasking it, and revealing its pointlessness.

That’s why Pope Francis never engages with Daesh’s claim to be religious, nor wastes time examining Islam’s supposed “problem with violence.” Daesh’s claim to purity and its attempt to yoke violence to divine sanction proves its atheism.

Francis is right: attacks such as yesterday’s exhibit not religiously-sanctioned power, but pointlessness. They are  — to use his word — “absurd.”

They may destroy lives, but they cannot construct anything of value or that endures. In that sense, their pathetic resort to the pretense of power that violence offers reveals only their powerlessness.

Conversely, the daily vulnerable business of living, moving and working — going about our tasks, unarmed and unafraid — reveals our power.

Getting up, dusting off, mourning the dead and then getting on with our jobs is the best public response to terror, and one that London is good at. We’ve had practice, and it works.

It won’t end Daesh, of course, or some version of it that persists long after it is vanquished in Mosul. If Israel annexes Palestinian land through settlements under the guise of emergency security measures, as the Trump administration seems happy for it to, terrorism will continue to haunt us.

And as long as Islam proves incapable of expunging the fundamentalism within, the attacks will return.

All we can do is try our best to detect them, and foil them; but when that fails, as it sometimes will, we must never be intimidated. The call to Londoners is to patiently endure, spurning the temptation to turn on each other; to serve those in need, building and healing in the places where there is destruction and blood.

That way we show that we are made according to God’s design, and that no amount of terror, however suddenly and brutally it strikes —  even at the heart of our government — can wipe that away.

It may not look like a successful anti-terrorist policy, but it’s the only one capable of lasting victory. It is God’s way, and He is in charge.