So, the Americans are minus one more Guantanamo Bay headache.

And Canadians will now start arguing in earnest about whether Omar Khadr was a child soldier, as the UN has categorized him, or a terrorist murderer.

One way or the other, politics is now colliding directly with the Canadian legal system, which is supposed to be immune to political considerations.

Public Safety Minister Vic Toews, who, one suspects, is no great fan of the UN, makes it pretty clear what the government of Canada thinks: "Early this morning, convicted terrorist Omar Khadr was transferred to Canadian authorities,” Toews told reporters on Saturday.

In case anyone missed his point the first time, the minister added: “Omar Khadr is a known supporter of the al-Qaeda terrorist network and a convicted terrorist."

• TIMELINE: Key moments in the Omar Khadr case

Well, “terrorist” has become a pretty pliable term these days. It’s a political invective that’s been stripped of meaning by overuse, which is why many news organizations simply avoid using it whenever they can.

As for governments, suffice it to say that both democracies and dictatorships tend to describe violent opponents as terrorists, and violent supporters as heroes.

Mujahideen E Khalq, an organization with a history of bombings and assassinations in Iran, both during the time of the Shah and after the 1979 Islamic revolution, was officially designated a terrorist group by the U.S. in the late 1990s.

But now that it has marshaled enough important people here in the U.S. to lobby on its behalf (and has pledged to give up violence), it is in the process of being removed from the official list.

Besides, keeping MEK on the list was starting to seem pretty rich, given that Iranian nuclear scientists keep dying at the hands of mysterious assassins.

Welcome back

In the case of Omar Khadr, it is probably worth noting that Toews avoided describing Khadr as a terrorist in the legal decision he signed authorizing Khadr’s return to Canada under the International Transfer of Offenders Act.

Omar Khadr at the U.S. military's Guantanamo Bay detention centre in Cuba in 2010. (Canadian Press)

Such documents require somewhat more precise language than “convicted terrorist” and “supporter of terrorists.”

The Toews’s decision stated: “Omar Ahmed Khadr is a 26-year-old Canadian citizen, first-time offender … convicted, pursuant to a guilty plea by him, of . . . Murder in violation of the law of war."

• PHOTOS: Omar Khadr

That’s correct, of course, as far as it goes. Khadr did plead guilty to throwing a hand grenade at an American special operations soldier on the Afghan battlefield in 2002, when he was 15 years of age.

As most people understand the word, a terrorist is defined as someone who deliberately targets civilians, not soldiers in battle.

But this soldier was part of the American invasion of Afghanistan, and those U.S. soldiers enjoyed a rather special legal status. They were empowered to capture and kill anyone who stood in their way, and Afghans, or anyone else on Afghan soil, were not allowed to fight back.

To do so was a crime under international law, at least as interpreted by the White House, and, in this case, murder in the eyes of the U.S., though it took two military commissions, a number of appeals and an act of Congress to establish the military’s right to charge him as they did.

Politically sensitive

Eventually, Khadr agreed to a plea bargain admitting guilt, but one that took place in rather special circumstances.

He had already served eight years in the Guantanamo Bay detention camp, and was facing the possibility of spending the rest of his life there if he didn’t plead guilty.

That’s not the sort of leverage most prosecutors enjoy, particularly when they are dealing with someone who was 15 at the time of the offence.

In fact, the maximum term in Canada for a young offender is 10 years, with a maximum of six years imprisonment.

Khadr, has already served nearly 10 years. His current sentence officially expires in 2018, though the expectation is that he will be paroled well before that.

The fact is, Omar Khadr is a politically sensitive offender (not to mention a young offender when he was captured), who has just arrived in a country that does not, or is not supposed to, distinguish offenders by political sensitivity.

We will probably soon see how the legal system feels about that.

Toews, in his decision, lists several issues that “caused him concern” in deciding whether to allow Khadr, a Canadian citizen, to finish his sentence in Canada.

Among them: that Khadr’s mother and older sister have openly applauded what he did in Afghanistan (would a judge be allowed to cite such a thing in considering punishment for any other 15-year-old murderer?); and that Khadr’s time in Guantanamo has radicalized him.

Toews asserts this last bit without evident irony.

Khadr, of course, would not have been radicalized in Guantanamo for anywhere near as long as he was had the government of Canada not for years resisted orders from its own courts to request his repatriation. (The Supreme Court, in fact, found that Canada had violated Khadr’s Charter rights by participating in illegal interrogation methods.)

And nowhere does Toews address the fact that Khadr was a toddler when his father first began indoctrinating him in jihadism.

Omar Khadr may well be a dangerous man now, at 26.

Perhaps he is even dangerous enough to merit incarceration at Millhaven Penitentiary, a grim fortress that houses some of the most violent convicts in Canada.

Certainly, though, he’s the only inmate at Millhaven serving time for something he did a decade ago when he was 15 years old.

And by Vic Toews’s own logic, Canada’s government has had something to do with making him the person he is today.