My preference is for the "traditional" (at least since Lester Pearson) role of Canadians as peacekeepers. I think sending in a military to "fight" in a country for 8 years creates a sense of occupation. It only recruits more Taliban.
I accept the need to strike hard in retalliation when the Taliban allow al Qaeda to strike out at targets around the world, but I don't buy sending over a hundred thousand troops to occupy the land for coming up on 9 years. The initial strike in Afghanistan was effective because it was a CIA operation on the ground coordinating Northern Alliance fighters with US Air Force planes that could bomb selected targets. These "foot patrols" in Afghanistan that result in deaths from IEDs is a sheer waste of human life. It is a policy of "national building" that is a complete waste of blood and treasure.