One by one, Conservative MPs in the House of Commons led by Prime Minister Stephen Harper voted late Tuesday to join the war in Iraq, passing a controversial motion that clears the way for Canadian CF-18s to embark on airstrikes in the Middle East. After two days of debate, the motion to launch a combat mission against the militants of the Islamic State of Iraq and Al-Sham (ISIS) passed 157-134. Some 155 Conservatives voted in favour of the motion, with the help of Independent MP Brent Rathgeber and Green MP Bruce Hyer, while the NDP and the Liberals were opposed. Liberal MP Irwin Cotler abstained from the vote. "We do not take this step lightly," Harper said in a statement following the vote. "It is imperative that we act with our allies to halt ISIL's spread in the region and reduce its capacity to launch terrorist attacks outside the region, including against Canada. "Our government has a duty to protect Canadians and to shoulder our burden in efforts to combat threats such as ISIL. We must do our part." Combat missions do not ordinarily require Commons approval, but Harper himself promised any combat mission, including airstrikes, would be subject to a debate and a vote. In a statement of his own after the vote, NDP Leader Tom Mulcair accused the Conservatives of "plunging Canada into a prolonged war without a credible plan," and said the motion which expressly permits airstrikes in Syria, too, with Syrian approval exposes Canada to a bloody civil war in that country. "Time and again, Conservatives have refused to answer clear questions and been evasive on critical details of this mission," Mulcair said. "It is impossible to have confidence in the judgment of a prime minister who sends Canada into an unclear mission for an unspecified period, in an undefined area, with uncertain utility." Canadian military officials in the region will now be tasked with ironing out the final details with allies so the first of up to six CF-18s, two surveillance aircraft, a refuelling plane and about 600 Canadian Forces personnel begin to arrive in the region. A senior government official said those discussions are expected to take about three weeks, and include figuring out where the Canadian aircraft will be based and how they will be integrated into the overall bombing campaign. Canada joins Britain, France, Denmark, the Netherlands and Australia as well as Saudi Arabia, the United Arab Emirates, Jordan and Bahrain in launching air strikes against ISIS. Canada's combat mission to Iraq will include CF-18 Hornet fighter jets, surveillance planes and support personnel for up to six months. The U.S. military is co-ordinating the allied effort, but Canadian officers will be responsible for running Canada's mission, all the way up to defence chief Gen. Tom Lawson. The U.S. has faced criticism for targeting not only ISIS forces, but also destroying such infrastructure as gas plants, power stations and grain silos. An unknown number of civilians have also been killed in the airstrikes. The CF-18s are expected to come from CFB Cold Lake in Alberta and the Polaris refuelling aircraft from CFB Trenton. The two Aurora surveillance aircraft could come from either CFB Comox on Vancouver Island, or CFB Greenwood in Nova Scotia. Postmedia News is reporting that Canadian military officials are in discussions with Kuwait to base the CF-18s and other aircraft there. Kuwait served as a staging area for Canadian military operations in Afghanistan during the latter years of Canada's involvement there. The mission will initially run up to six months and be limited to bombing targets in Iraq. However, Prime Minister Stephen Harper has said the mission could be extended and expanded into Syria if the Syrian government gives its permission. With Tuesday's vote in the House of Commons, Canada is sending its military into its third combat mission in less than a decade. The Canadian military fought the Taliban in Afghanistan between 2005-2011, and participated in a NATO-led bombing campaign in Libya in 2011. The mission has become a lightning rod for political debate, with the NDP and Liberals accusing the Conservative government of dragging the country into an ill-advised war with no easy exit. The NDP, in particular, has pointed to the current situations in Afghanistan and Libya, as well as the 2003 U.S. invasion of Iraq, as proof western military intervention has actually contributed to instability. Following Tuesday night's vote, NDP leader Tom Mulcair issued a statement that claimed the Conservative government was "plunging Canada into a prolonged war without a credible plan to help victims of ISIS terror." NDP Leader Tom Mulcair is applauded in the House of Commons on Friday. "They have also opened the door to Canadian involvement in Syria's bloody civil war," Mulcair added. Both the NDP and Liberals have suggested Canada's focus should be on humanitarian aid, though they differ on whether any Canadian military mission is required. Mulcair had tabled an amendment to the government's plan that would take combat operations off the table, and instead emphasize humanitarian aid, investigation of ISIS war crimes and the transport of weapons to Iraq. It was defeated Tuesday night despite support from the Liberals, Bloc Quebecois and Green Party leader Elizabeth May. The Liberals have supported the deployment of 69 special forces troops to northern Iraq to provide advice and training to Iraqi and Kurdish forces fighting ISIS, and Liberal leader Justin Trudeau has left open the possibility of his party supporting a combat mission in the future. "We will see what will be required in the coming months," Trudeau told reporters before the vote Tuesday. "But now, for this vote tonight, the prime minister has failed to demonstrate transparency and accountability for sending Canada into war." With U.S. officials warning the war against ISIS could take years, the conflict now becomes a significant political issue for all three major parties as the country heads towards a federal election next year. Putting an initial six-month limit on the combat mission means Canada can pull out if the airstrikes either do their job and eliminate ISIS as a threat, or are found to be ineffective against the group. But it also gives the Conservative government an out if popular opinion turns against the effort. Several polls in recent weeks have suggested the majority of Canadians support airstrikes against ISIS, but all three parties know those sentiments could change before the election. Tuesday's vote came after the Conservative government limited debate on the mission by invoking what is called closure, or time allocation. Government House Leader Peter Van Loan said in an email the move was necessary to prevent the debate from dragging out indefinitely. But opposition parties accused the Conservative government of abusing its power to limit debate by invoking closure a record number of times over the years. The government has limited debate on everything from budget bills to free-trade agreements. Opposition parties also said the move raised fresh questions about the Conservative government's commitment to transparency when it comes to sending Canadian military personnel into war against ISIS. Just before the vote, Liberal MP Irwin Cotler announced he would be abstaining, saying he supported the need for an international response to the threat posed by ISIS under the auspices of the Responsibility to Protect, but that the government did not provide enough detail of its plan for him to support it. Independent MP Brent Rathgeber and Green Party MP Bruce Hyer voted with the Conservatives in supporting the government's plan for sending Canadian forces into combat in Iraq. Postmedia News and The Canadian Press