Never mind the matter of why the failed assassin Jaspal Atwal would be invited to any sort of diplomatic reception, let alone one starring Prime Minister Justin Trudeau and his wife. Political parties can be venal and willfully blind to ugly realities in pursuit of votes, and that should be no surprise.

The better question is this: how in heaven's name was that man allowed to set foot on a passenger aircraft, in an age of no-fly lists so strict that babies with names similar to violent extremists are denied boarding?

The answer is that Jaspal Atwal is not on the list, and almost certainly never was, despite the fact that by any of the definitions law enforcement uses to define a terrorist, Jaspal Atwal is a terrorist. And not an aspirational one, either, like some of the clumsy fools who have been reeled in over the years by overweening government stings.

No, Jaspal Atwal belonged to a cohort of Sikh extremists who, from their base in Canada, fought a violent war against the government of India in the '80s. Their hatred may very well have been justified – the Indian government was as ruthlessly vicious as they were.

Air India bombing

But the facts are not arguable: Atwal's fellow travellers bombed a jumbo jet, killing 329 innocent souls, over the North Atlantic in 1985. And they narrowly failed to bring down a second airliner, which instead exploded on the tarmac at Tokyo's main airport, killing two baggage handlers.

Atwal himself tried his very best a year later to murder a high official of the Indian government on Canadian soil. He failed only because his target, Malkiat Singh Sidhu, managed to feign death, despite the two bullets Atwal and his confederates had already fired into his body. (Five years later, other Sikh extremists finished the job for Atwal, murdering Sidhu near his home in Moga).

In any case, in their day, Atwal and his ideological colleagues were in the same league as, and in fact even more deadly than other far more famous groups: the Baader-Meinhof gang, the Shining Path, Black September, the IRA, the Red Army Faction.

Certainly, they were a far more lethal threat than the disturbed homeless man who shot a reserve soldier in the name of Allah in Ottawa nearly four years ago, and was subsequently shot dead himself in the Parliament buildings, providing hawks with justification for a controversial new anti-terrorist law.

Sikh extremists were a closed, fanatical bunch, and virtually impossible to penetrate, as Canada's nascent intelligence service learned. They were CSIS's first and greatest failure; Canada's international shame, a former CSIS chieftain called them.

And yet there was Atwal, posing with a beaming Sophie Grégoire Trudeau, at a Canadian diplomatic reception in India last month, having boarded a plane and flown to India a few days earlier.

Sophie Trudeau and Jaspal Atwal pictured at a film industry influencers event with Indian film stars in Mumbai Feb. 20. (Name withheld by request)

The explanation for the invitation is pretty obvious: Atwal, since his release from prison decades ago, has remained active in Sikh politics, and became prominent in the apparatus of the Liberal Party of Canada, which depends heavily on the Sikh vote. Atwal was in fact invited to the reception by a Sikh Liberal MP, and he has been posing for photos with Liberals, federal and provincial, for years.

It is unlikely that any effort was made to vet Atwal's name with CSIS. His name is in the CSIS system, and would have been instantly flagged.

But the explanation for his ability to get on a flight to India is far more interesting. In search of that answer, I spoke recently to four former Canadian intelligence officers from the era of the Sikh wars. All, as you'd expect, were disgusted at the photo of Atwal in India. Three of them once had roles overseeing Canada's no-fly list.

The list, they say, is exceedingly short, at least compared to the American list. It is curated by Transport Canada, with input from CSIS and the RCMP, and it remains secret. In order to be placed on it, said one ex-spy, authorities have to make the case to a multi-departmental committee that the individual poses a threat to aviation — a bar one of the agents who participated in the committee meetings felt was far too high. Often, he said, CSIS would come away frustrated in its efforts to have an individual placed on the list.

And especially since 9/11, the focus of the list, and of our intelligence agencies, has been just about exclusively on Islamic jihadists. Its greatest recent growth has been fed by names of Canadians who have flown off to fight in Syria.

Canada's spies are bound tightly to their American counterparts, and respond to American priorities, and, says one of the ex-agents I spoke to, the Americans never really cared about Sikh extremists. As far as they were concerned, the Sikhs were just killing each other, which was fine with them.

(It should be noted here that of the 329 killed in the Air India bombing, the vast majority carried Canadian passports. None was an American citizen).

All four of the former intelligence officers I spoke with reckoned that Atwal cannot possibly be on the American no-fly list either, because Canadian carriers are extremely skittish about boarding anyone on that list, even on a flight not flying into American airspace.

Let's go beyond Atwal, though. Here is another excellent question: What about Inderjit Singh Reyat, who served time in prison for actually building the bomb that brought down Air India Flight 182 in 1985, and who is now free on parole? Is he on our no-fly list?

Or Ajaib Singh Bagri? Or Ripudaman Singh Malik? Both those men were early, prominent members of Babbar Khalsa, the group that hatched the airliner bombings, and while they were acquitted in court of conspiracy and murder, any ISIS- or al-Qaeda-style jihadi with their credentials would likely never fly again. Are they on the Canadian list?

It is worth considering that Sikh extremist groups – Babbar Khalsa, or the International Sikh Youth Federation, to which Atwal belonged – have more in common with the IRA, or the FLQ in Quebec, than with, say, ISIS.

Like the IRA, the Sikh groups are not regarded as terrorists, and indeed warmly regarded, in certain sectors of their diasporas. The IRA enjoyed considerable fundraising and popularity in cities like Boston and Montreal back in the days when it was carrying out bombings of British targets, and the portrait of Talwinder Singh Parmar, the founder of Babbar Khalsa and mastermind of the Air India bombing, still hangs in Sikh religious centres in British Columbia.

Paul Rose, the leader of the FLQ cell that kidnapped and strangled Quebec cabinet minister Pierre Laporte in 1970, entered politics after his release from prison and was even a nominated candidate for the New Democratic Party of Quebec in 1992. Quebecers took a much more sympathetic view of him than English Canadians. Atwal is sort of a Sikh version of Paul Rose.

But even if he evaded placement on the no-fly list, and wangled an invitation to a prime ministerial event, there is one more puzzling question about his visit to India: Why would the Indian government have let him in?

The Indians despise Sikh separatists, and agents of the RAW, India's intelligence agency, have been caught repeatedly operating against Sikhs on Canadian soil (If you can't deal with these bastards, we will, RAW reportedly once told CSIS).

All of the ex-agents I spoke to had the same theory: Atwal, they assume, had elected to cooperate with Indian intelligence. That, and a decision by the current Indian government to pursue some sort of rapprochement with the Sikh diaspora – the Khalistani separatist movement in Canada is now all but moribund – would explain his ease in obtaining an Indian visa.

Lucky fellow, our Mr. Atwal. Time has passed, and memories have faded. Perhaps the men currently sitting in cages in Guantanamo Bay have some hope after all.

But perhaps, just out of an abundance of caution, it would be better to keep them off airplanes.

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