The news that the Canadian Security and Intelligence Service and the Royal Canadian Mounted Police had arrested two men for alleged involvement in an al Qaeda-linked terror plot, and that further arrests are expected today, is an important reminder of the need for continued vigilance regarding terrorists attacks in North America. It is also proof that Canada takes the ongoing threat of terrorism seriously, and is working proactively to counter it.

Little is known about the plot alleged to have been planned by Misbahuddin Ahmed, an x-ray technician working for an Ottawa hospital, and his confederates, but this is not the first time that Canada has encountered terrorist activity within its borders.

The most deadly terrorist act in Canadian history was the 1985 bombing of Air India Flight 182, on its way from Montreal to London and then on to New Delhi and Mumbai. A twenty-year Canadian prosecution following the incident, which killed 329 people, resulted in just one conviction (on a guilty plea) for manslaughter. Earlier this summer, a commission of inquiry headed by former Canadian Supreme Court Justice John Major found that a "cascading series of errors" by Canadian security officials in a poor investigation had contributed to the failure to successfully convict other suspected conspirators. Major recommended new resources to strengthen terror-related investigations and prosecutions. The Harper government responded favourably, as did Canadian security services.

The 1993 World Trade Center bombing was a second wake-up call for Canadian officials. The U.S. Federal Bureau of Investigation (FBI) discovered that prior to the attack the mastermind behind the terror attack, Sheikh Omar Abdel Rahman, had traveled to Los Angeles, Chicago, Detroit, Toronto and Montreal to raise funds and recruit followers at Islamic centers and mosques. The FBI and the RCMP collaborated on the investigation, finding clear evidence that Abdel Rahman's network – not yet identified as part of al Qaeda – extended into Canada.

Two years later, Canada's infamous Khadr family came to the attention of Canadian authorities. Family patriarch Ahmed Saied Khadr, an Egyptian-born Canadian citizen with a computer science degree from the University of Ottawa was arrested in Pakistan for his role in a truck bombing of the Egyptian embassy in Kabul. Canadian Prime Minister Jean Chrétien lobbied his Pakistani counterpart Benazir Bhutto to release Khadr on a state visit in 1996, but the family did not repay Chrétien's trust. Ahmed Saied Khadr and his son Abdulkareem were killed in Afghanistan in 2003, and Khadr's son Omar is on trial for the murder of a U.S. Army medic in Afghanistan.

In 1997, New York City police raided a Brooklyn apartment and caught two men, Ghazi Ibrahim Abu Mezer and Lafi Khalil, in the act of preparing explosive devices they intended to detonate on the New York City subway. A subsequent investigation by the U.S. Department of Justice found that Abu Mezer and Khalil had originally emigrated from the Gaza strip (with lengthy Israeli arrest records) to Montreal where they applied for refugee status. The pair entered the United States illegally from Canada, crossing on foot from British Columbia to Washington State and from Alberta to Montana on different occasions before coming to New York. It was further proof that terrorists were operating on Canadian soil.

In December of 1999, Algerian-born Montreal resident Ahmed Ressam was arrested attempting to enter the United States from British Columbia in what became known as the "Millennium Bomber" plot. Ressam planned to set off his explosives at the Los Angeles International Airport.

By the time of the September 11, 2001 terrorist attacks in the United States, Canada's security services had made significant progress in upgrading their surveillance and response capabilities related to possible terrorist threats. However, the spectacular nature of these attacks led to further upgrades and a higher priority for terrorist threats.

A significant challenge for Canada after 2001, as for other western democracies, was to address the difficulties of bringing terrorism cases to trial in the Canadian courts. The admissibility of evidence, the standards of proof for an arrested plot, and respect for the legal rights of the accused all presented significant problems in light of Canada's Charter of Rights and Freedoms and the protections it affords to citizens and non-citizens on Canadian soil.

Mohammed Momin Khawaja, a Pakistani-born Canadian citizen who, like the Khadr family and those arrested this week was living in Ottawa, was accused of involvement in an aborted 2004 plot to bomb the London Underground. Khawaja was the first individual to be tried under Canada's anti-terrorism statute, and after being arrested in 2004 he was convicted in 2008.

The "Toronto 18" terror plot that came to light in 2006 involved plans to for rented trucks packed with explosives to be used to blow up prominent Toronto buildings and an Canadian military base, as well as a more graphic threat to behead Prime Minister Harper. The accused members of this terror ring were, according to prosecutors, hoping to prompt Canada to withdraw its troops from Afghanistan – making them one of the first plotters to make Canada the intended target of their attacks. In addition, the majority of the group had been born in Canada making it a case of home-grown terror. The investigation revealed the existence of a terror training camp in rural Ontario. Although seven of the 18 had the charges against them dropped or stayed (some were minors when arrested), a number of solid convictions has resulted from the prosecution and defense attorneys' charges of possible police entrapment were investigated and found to be groundless.

Despite the progress Canada has made in its efforts to investigate and combat terrorism, many Americans, including policy makers, have retained a false impression that Canada is not taking terrorism sufficiently seriously.

In part, this impression is driven by the stereotype of Canadians as decent but naïve Boy Scouts less wordly and less tough than Americans. This is nonsense, but difficult nonsense to refute.

Another part of the problem is that Canadian public diplomacy after September 2001 focused defensively on convincing Americans that the rumors of a Canadian link to the 9/11 attacks was false. While true, this narrowly-constructed defense rang hollow with U.S. security professionals familiar with the case history listed here. It was as though Canada was claiming innocence on a technicality, and in denial about the larger problem.

One more handicap for Canada was the media lionization of Maher Arar, a Syrian-born Canadian deported by the United States to Syria after Canada refused him re-entry following a trip to the Middle East, and Omar Khadr, Canada's sole remaining citizen in U.S. detention at Guantanamo. Arar claims that he was falsely denied re-entry to Canada, had no involvement in terrorism, and was tortured in Syria. The Canadian government, following a public inquiry, admitted that it was wrong to deny Arar re-admission and paid him $10 million (Canadian) in compensation. The United States continues to view Arar as a risk, and has him on the no-fly list and will not permit him to enter the United States. For some Canadians, Arar is a martyr of the war on terror, a victim of abuse. He is now an active public speaker across Canada, addressing anti-war rallies. Meanwhile, because Omar Khadr was 15 years old at the time of his arrest, his defenders in Canada promote him as a "child soldier" who must be excused from responsibility for his crimes. To Americans, the sympathetic media coverage of these two individuals in Canada appears to reflect a cluelessness on the part of Canadians when it comes to the terror threat. This is unfair: a silent majority of Canadians remains skeptical of the innocence of Khadr as well as Arar, the protestations of peace activists to the contrary. However, where Americans tend to voice their disagreement loudly, Canadians voice theirs with quiet contempt, which many Americans wrongly interpret as support.

The coming days will likely produce more details about the individuals arrested in Ottawa and what their intentions are alleged to have been. Without prejudging the merits of these cases before the evidence is in, it is time for Americans to credit Canada with seriousness and resolve against al Qaeda and terrorism that it has earned. More widespread U.S. respect in this regard is overdue.

Christopher Sands is a Senior Fellow at the Hudson Institute and a member of the Research Advisory Board of the Macdonald-Laurier Institute.

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