LONDON — Sudden attacks on innocent people are not a new phenomenon. When they happen, there is a tendency to say, “This changes everything.”

Sometimes it’s true, as in the 9-11 attacks. Sometimes it feels true because our memories are short. Her Majesty Queen Elizabeth II must have a long memory, giving deep perspective. The killings of innocents during the Troubles in Northern Ireland, particularly the murder of Lord Mountbatten, must still feel recent to her. Someone plowing his car into pedestrians likely doesn’t feel, to her, like an event that changes everything.

Maybe that’s why the flag over Buckingham Palace was at full staff on Sunday. I was startled to see it flying with no sign of mourning. Then I started noticing that not all the flags around London were at half-staff.

That was only one of the obvious differences between how our societies and our parliaments responded. There was no moment of silence in the British Parliament for those who had died until Wednesday March 29 — five days after the murders. In fact, when I attended proceedings in the Commons and the House of Lords on Monday, the business of the day proceeded without reference to the events of the previous Thursday.

In the House, the bus bill was debated, with Speaker Bercow in high spirits, chiding one member for being a “cheeky fellow.” In the House of Lords, a stately debate proceeded on preparedness for a cruise ship calamity at sea.

Is it the famous stiff upper lip? I thought the public mourning over Diana had put an end to the British reserve in grief-sharing.

The public and media reactions were closer to Canada’s. The flowers piled up outside Westminster and at every spot along the Westminster Bridge. The hourly news continued to focus on updates about the killer and his family, as well as those killed and their families.

The similarities in the events themselves are striking. Many aspects of the October 22, 2014 Parliament Hill attack in Ottawa and the March 22, 2017 London attack are similar.

Canada had no public inquiry. We still need one. Changes to consolidate security services under the RCMP were hasty, violating centuries of respect for the principle that the government should never control security for the country’s Parliament. Canada had no public inquiry. We still need one. Changes to consolidate security services under the RCMP were hasty, violating centuries of respect for the principle that the government should never control security for the country’s Parliament.

In both cases, the parliaments were full of MPs and staff. We were both in lockdown. I compared notes with my colleague, the Baroness Jones of Moulsecoomb, the only Green Party peer. (Despite the grand title, she insists that I call her ‘Jenny’.) She shepherded me through the Peers’ entrance, pointing out luminaries — the peer who wrote House of Cards, Lord Michael Dobbs, and later over tea, musician Brian May of Queen — the band, not the regal one. (May is keen on stopping the badger cull).

Jenny shared her photo of the hundreds of peers, MPs and staff held in lockdown in the 1,000-year-old Hall of Westminster, built by the son of William the Conqueror. The British Parliament was locked down for five hours. Jenny sympathized with our experience in 2014; we were in lockdown for twice as long.

In both instances, only one person was involved in the attack. No accomplices or links to organized terrorist cells appear to exist in the London attack, at least at this point. In both cases, the seat of government was the target — although in historic terms, neither attack rivalled the Gunpowder Plot.

In both cases, an unarmed (and magnificent) public officer was killed. Both men — Cpl. Nathan Cirillo in Ottawa, PC Keith Palmer in London — were more accustomed to posing for photos with tourists than facing an armed intruder. More people were killed and injured in London than Ottawa due to the killer having the funds to rent an SUV.

In both cases, the horrific tragedies were acknowledged as events that could have been far worse. Thank heavens neither man had access to the kind of semi-automatic killing machines that mass murderers have used in attacks in the United States.

The killer in London was equipped with an SUV and a knife — enough to kill four people and injure 40. He was a violent man with a criminal history. He allegedly was radicalized in prison. It is clear that, for both killers, had prison services focused on this risk, tragedy might have been averted. The Ottawa killer certainly was desperate enough to get himself arrested and beg a Vancouver judge to get him help mental health counselling.

Was this terrorism? Was the murder of the wonderful British Labour MP Jo Cox a terrorist attack? If one is, then why not the other?

The Speaker of the U.K. Parliament has announced two separate inquiries. They are to be conducted by independent security experts. The results will be public. And here is the biggest difference between the Canadian and British experiences: transparency.

Canada had no public inquiry. We still need one. Changes to consolidate security services under the RCMP were hasty, violating centuries of respect for the principle that the government should never control security for the country’s Parliament. The hero of the day, former Sergeant at Arms Kevin Vickers, was quickly dispatched to Ireland as ambassador.

It’s not too late to demand an inquiry. Memories are particularly short, and history more likely to repeat itself, when we refuse to examine and learn from experience.

Elizabeth May has been in the U.K. all this week for the quadrennial Global Greens Congress. [email protected]

This article appeared originally in Policy magazine.

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