Stephen Harper has pledged Canada will stick with the mission in Libya until it ends, but there's still the question of what ending he means.
Is it over when Moammar Gadhafi is caught, or when the remaining strongholds of his supporters surrender, or when the interim government has established a stable writ across the country? They could be very different targets.
It's crucial for Mr. Harper to spell out his goal if he extends the Libya mission again. If he learns from the past, he'll declare victory when those last strongholds fall.
At the moment, both NATO and Canada are working under a mandate that ends in less than three weeks. The understanding within the alliance, according to officials from key allies, is that the NATO mission will end when pro-Gadhafi strongholds have surrendered to the interim government of the National Transitional Council.
There's hope that will be soon, but should it fail to happen before Operation Unified Protector's Sept. 27 deadline, NATO, and Mr. Harper, could very well choose to extend it.
But there's another possible end that still worries allies: Gadhafi opponents will come unglued, the NTC's interim government won't establish a stable government, and factions will start battling.
From NATO's point of view, the mission in Libya has gone well – much better than expected even in mid-August when generals from Canada and other countries didn't expect the rebels to take Tripoli any time soon. The NTC has so far managed a good degree of unity and is administering areas where it has solidified control.
But the recent history of Western involvement in overseas wars has seen conflicts go on far past the date when they were thought to be mostly over. One lesson learned from Afghanistan was the importance of setting clear, realistic goals.
In the past, Western nations have never just limited themselves to a heavy air campaign and gone home. The closest thing to the air-only war was the Kosovo campaign, which ended with a ceasefire and a peacekeeping force. The first Gulf War was followed by a no-fly zone for more than a decade.
At the moment, NATO allies seem to have a framework for how the mission should end. They argue that once pro-Gadhafi strongholds such as Bani Walid, Sirte and Sabha have been taken, pro-Gadhafi forces won't have the base or the means to threaten civilians. That will be the signal to wrap up Operation Unified Protector, with its air strikes and its naval blockade.
Even after surrender, some think NATO should stay a little longer, for something like a no-fly zone mission: lesser-scale surveillance from the air, with the capacity to strike pro-Gadhafi remnants, or factions, that may attempt to sabotage the interim government's hold by hitting oil wells in remote areas.
"If NATO packs up in three weeks' time on the assumption that all the major resistance is gone … it would be a very bad idea to expect the new authorities to be able to handle it," said Shahshank Joshi, an analyst with the Royal United Services Institute in London. Even so, Canada's frigate and half-dozen fighters aren't key to that task.
Then there's the gloomy scenario: Anti-Gadhafi factions will split into fighting. The NTC doesn't have complete control of all elements now, and there's still some fear of a split. The NTC would probably then turn to NATO for help, one Western official noted, but it doesn't fit the mandate to protect civilians. Would some allies feel a responsibility to stabilize the country?
Some already predict a need for ground troops. Among others, Paul Bremer, the former U.S. administrator in Iraq, argued there's doubt the NTC can establish security or whether Libyan factions can agree on things such as laying down arms. If not, he said, "some kind of international stabilization force will have to go in."
NATO countries, and Mr. Harper, insist they won't send ground troops. But murky goals have led to mission creep before. Libya's NTC has said it doesn't want foreign troops. If things change, it should be remembered why: They are struggling to establish legitimacy in Libya. Foreign troops would likely undermine it. It could be a destabilizing force. It would no longer be the mission to stop a murderous Gadhafi, and would require a clear, compelling goal.
The best tool Western allies have to prevent that splintering is money, with some technical assistance, to bolster the NTC not just as the sole legitimate authority, but one with resources. As they gradually release billions in frozen assets to the NTC, it will hopefully strengthen its capacity to govern and provide incentives for factions to work with it.
And with the military mission apparently mostly over, any extension requires a goal for the end: calling back the fighters and the warship when the last major Gadhafi strongholds are gone.
Campbell Clark writes on foreign affairs from Ottawa