The defence minister would not go so far as to say the Americans asked Canada to expand the scope of its airstrikes outside of Iraq, but did indicate that Washington left the option open for consideration.
"Let me put it this way: We have conversations back and forth and they made it clear that they thought our precision-guided munitions would be helpful," Kenney said.
"They obviously respect whatever sovereign and political decision the government takes, but on a military level they made it clear that precision-guided munitions, carried by the RCAF, would be useful to joint air operations in Syria."
The U.S. and some of its Arab allies — notably Jordan and the United Arab Emirates — are already conducting airstrikes in Syria against the Islamic State of Iraq and the Levant.
They all use the U.S.-made weapons — including Joint Direct Attack Munitions, or JDAMs, and so-called Paveway bombs — to the point where the military commander of NATO complained last year European allies don't have enough of them.
Britain, France and Australia are also conducting airstrikes, but not in Syria. The Harper government had initially restricted Canadian warplanes to Iraq only, but that changed Tuesday with the introduction of a motion to expand and extend the mission until March 30, 2016.
Kenney, Foreign Affairs Minister Rob Nicholson and Prime Minister Stephen Harper faced a storm of demands Wednesday to justify the bombing of Syria under international law.
In the Commons, Harper leaned on the U.S. argument — made to the United Nations — that Syrian dictator Bashar Assad had lost control of his territory, that ISIL represents a clear imminent threat to its neighbours, and that the Iraqi government specifically asked Washington to take action.
Kenney took it a step further, saying he has a legal opinion from the military's judge advocate general justifying the airstrikes under Article 51 of the UN charter.
That provision says a country can take individual or collective self-defence action if a member is under armed attack, but the invocation of that clause is usually followed by an international resolution authorizing force.
Even still, Canada has a right to defend itself — and extremists returning from the civil war battlefields of Syria personify that threat, Kenney suggested.
Legal experts in Washington, who've argued against the U.S. bombing campaign, say the self-defence justification requires an imminent threat, otherwise it's a preventative war — something the international community does not look kindly upon.
NDP Leader Tom Mulcair wondered during question period whether Canada had notified the UN or received a formal request from Baghdad to drop bombs in Syria, a question Harper studiously avoided answering.
"Once again, the government is pursuing this action on exactly the same legal basis as its allies," Harper told the Commons.
"I'm not sure what point the leader of the NDP is ultimately making. If he is suggesting that there is any significant legal risk to lawyers from ISIL taking the government of Canada to court and winning, the government of Canada's view is that the chances of that are negligible."
The remark left Mulcair incredulous that he lives in a country "where that sort of idiocy passes for argument."
Liberal Leader Justin Trudeau said he's worried the plan to broaden the mission has not been properly thought through.
Just what kind of added risk CF-18s pilots will face is unclear. They will have to fly further during Syrian missions; the strategy for keeping out of the reach of Assad government forces remains vague at best.
Kenney said military planners have assured him that Syria's Soviet-era air defences are not concentrated in the western portion of the country, where Canadian jets will eventually be bombing.
Nor do ISIL extremists have anti-aircraft weapons capable of hitting high-altitude jet fighters, he added.
— With files from Joan Bryden
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