The Conservatives want to extend Canada's involvement in airstrikes against ISIL militants in Iraq — and expand the mission into Syria — for up to a year, in order to help stop the march of a "genocidal" group they consider a threat to domestic security.
A vote on the government's motion is scheduled for shortly after 8 p.m., but it's likely just a formality, given the Conservative majority in the Commons.
MPs will first have to decide whether to support any of the amendments made by the NDP, which wants to end Canada's participation in airstrikes all together and focus instead on humanitarian measures to ease the crisis that has plagued Iraq and Syria since last year.
On Tuesday, diplomats from around the world are set to meet in Kuwait to focus on collecting the billions the UN says it needs to ease the humanitarian crisis in Syria alone, where 200,000 people have been killed and millions displaced by the ongoing civil war under President Bashar Assad.
The Conservatives say the plan to allow Canadian fighter jets to bomb ISIL targets within Syria would not be to prop up Assad. Islamic State fighters are using the eastern part of that country as a base and cannot be allowed to do so, they argue.
The opposition has argued that Canada lacks the legal basis to expand airstrikes into Syria without that country's express consent, something the Conservatives had said last year they would seek before expanding the mission.
The government's premise that those strikes are legal because they are in Canada's self-defence does not hold water, the opposition says — an argument supported by the fact no other Western nation besides the U.S. is involved there.
"I don't see any efforts being made to build a coalition of Western allies," NDP MP Charlie Angus said during debate Monday.
"What we have is the United States as well as Arabic countries who've been known to be spending millions of dollars fighting a proxy Sunni-Shia war in Syria. Those are our so-called allies."
Liberal MP Irwin Cotler, well-respected by all MPs on matters of international law and human rights, has said he'll abstain from the vote in part because of the government's Syrian approach.
"In October, I was unable to support the government's motion because of the Prime Minister's statement that Canada would give a veto to the criminal Assad regime," he said in a statement.
"I remain unable to support the government in this matter because its proposed expansion of Canada's mission continues to allow Assad to assault Syrian civilians with impunity."
Last October, 157 MPs voted to send CF-18 fighter-bombers, two CP-140 surveillance planes, one refuelling aircraft and 600 personnel, on top of the 69 special forces advisers already on the ground working with Kurdish peshmerga forces.
The current motion proposes the exact same contribution, only for a maximum of one year, and authorizes airstrikes in Syria.
The extended timeline is in part so that a renewal wouldn't come during this fall's federal election.
In introducing the motion two weeks ago, the prime minister said the Canadian contribution had made a difference so far, although he was careful to avoid suggesting the threat had in any way been mitigated.
"The territorial spread of ISIL, something occurring at a truly terrifying pace in the spring and summer of last year, has been more or less halted. Indeed, ISIL has been pushed back somewhat at the margins," Harper said.
Liberal Leader Justin Trudeau said the end goal for the mission isn't clear and that's one of the reasons his party can't support it.
"Will our involvement in this mission end next March, or was the foreign affairs minister being more truthful when he explicitly compared this war to Afghanistan, saying that we are in this for the longer term," Trudeau said.
"We cannot allow rhetorical appeals to moral clarity to disguise the absence of a plan."
In the fall, 134 MPs had voted against the deployment, and it became a polarizing political issue in the House of Commons over the last few months, with the Conservatives accusing the opposition of wanting to do nothing in the face of global terrorism.
Both opposition parties, however, say they've provided alternative solutions.
The Liberals have suggested that more Canadian soldiers be deployed in a training capacity, drawing on the experience they gained doing similar work in Afghanistan.
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