There have been 16 major vehicle attacks around the world since 2001.

This was by far the deadliest yet in Canada and is raising questions here in capital about keeping citizens safe on our streets.

It's happened around the world; guns and bombs being replaced by a different kind of weapon:  trucks being rammed into pedestrians. It is forcing police and politicians to reconsider how to protect us.

A beautiful sunny day draws the crowds in Ottawa’s Byward Market.  And, after yesterday's attack in Toronto, it draws questions, too, about security.

“Just keep walking,” says one woman, “but always look behind.”

This is the new mantra, perhaps, in a new era where vehicles are used as weapons of mass destruction.

“You're walking on the street and you never know what's going to happen,” says Tammy McGarry, an Ottawa resident.

“It's hard to cross that line into fear, I guess,” adds Bill Pearce from Orangeville.

But we have crossed that line.  Look at the security measures around the U.S. embassy now.  And bollards are about to be installed at Ottawa city hall later this year. 

The tougher challenge is how to keep what are called "soft targets” like you and me safe.

“We won’t skimp on security if we feel there is a need for other protective devices,” says Ottawa Mayor Jim Watson, “We will invest in those because we don't want to see what happened in Toronto happening here and harming anyone.”

Elliot Tepper is an expert in security and terrorism, a Senior Research Fellow at Carleton University’s Centre for Security and Defence Studies and says the challenge for Canada will be balancing that security with freedom.

“We want our freedom, we want to have sidewalk cafes,” he says, “We want to be able to go to Lansdowne Park but at same time, we want to be protected. That is the challenge we now face; that Canada is once again being reminded we aren't immune from the forces that go on in our world.”

Nowhere is that protection more evident than on Parliament Hill, the scene today of a rally to commemorate the 103 anniversary of the Armenian Genocide and a counter-rally by the Turkish community. The House of Commons was, of course, the scene of a terrorist attack in 2014.  Today, any violence was tempered by a huge police presence and a physical barrier between the Turks on one side and the Armenians on the other.  But that couldn't stop the verbal bombs being launched.

“Our worry,” says Selami Sahin with the Turkish Association of Canada, “is that terrorism is back from the Armenians, the Asala, which controls terrorism and they carried out the events in the past.  They rented a U-haul van and one was rented yesterday so is someone backing up this issue or is he acting on his own?”

“Nobody here had foreknowledge or association with this attack,” countered Shahen Mirakian with the Armenian National Committee of Canada, “and we've condemned it in strongest terms.”