Manley nailed it right off the bat in his Foreword on the Independent Panel's Report on Canada's Future in Afghanistan. The rest flows from this:
We like to talk about Canada’s role in the world. Well, we have a meaningful one in Afghanistan. As our report states, it should not be faint-hearted nor should it be open-ended. Above all, we must not abandon it prematurely.
Rather, we should use our hard-earned influence to ensure the job gets done and gets done properly.