There is a coldly calculating, self-interested rationale underlying the withdrawal of Royal Canadian Air Force CF-18s from the war against the Islamic State of Iraq and the Levant. But for reasons of diplomacy and tact, it’s not one the federal Liberals can easily acknowledge.

For months, since early in the recent federal campaign, Trudeau has offered variations of the same answer, when asked to explain this move; Canada is re-examining its contribution to the anti-ISIL coalition, is determined to be a constructive member, but wants to engage in a way that plays to this country’s strengths. Training soldiers and police, providing relief and humanitarian aid, the Liberals say, are things Canada does exceptionally well. Therefore, we should focus our efforts there, not on combat.

Trouble is, it’s a circular argument. It assumes humanitarian aid and combat are mutually exclusive. In fact, as years of simultaneous war-fighting and reconstruction in Afghanistan showed, humanitarian work and training can only occur where there is security, which is established by force of arms.

In the case of the war in northern Iraq and Syria, the situation is rendered more complex by the Western alliance’s — read, the United States’ — continuing reliance on air power alone, rather than large numbers of its own ground troops. Local forces, mainly Kurdish Peshmerga and the Iraqi army, have until now provided the infantry. The U.S.-led air campaign is intended to provide those local soldiers with cover — an umbrella beneath which they can move unimpeded, but their enemy cannot.

Hence the flaw in the argument that “air strikes achieve nothing.”

Hence, Trudeau’s remark to the Ottawa Citizen’s Mark Kennedy in early October: “We know there is a very real possibility that the next president is going to have to make a decision about sending ground troops into the area …”

Though no one in the Trudeau cabinet, least of all the PM himself, would say this aloud out of deference to Obama, the cancer of ISIL and the Syrian refugee crisis have their root in American strategic mistakes. President George W. Bush’s catastrophically misguided invasion of Iraq in 2003, and the subsequent bungling of the occupation, are of course not Obama’s fault. But they are, from a certain perspective, America’s responsibility to redress.

Canadian soldiers contributed willingly, in many cases heroically, to the mission in Afghanistan. But as soon as it became clear the Afghan government itself was unwilling or incapable of holding up its end, round about 2010, the former Stephen Harper government quickly lost its appetite for the mission, predicated on Canadians doing the same. Harper was not politically wrong in that assessment.

The Trudeau Liberals are mindful that Jean Chretien’s decision to keep Canada out of Iraq in 2003 is remembered as one of his crowning achievements. They are thus trying to craft a strategy that keeps Canada in the anti-ISIL coalition, but far from any implied commitment to deploying soldiers in a future U.S.-led ground war. The long delay in developing a plan for a training mission, it’s logical to assume, is related.

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