When Canada first deployed to Afghanistan (Kandahar in 2002) DFAIT listed three "aims" or "roles" (I cannot remember what they called them) which were, roughly:
1. To
defend Canada by helping to replace the Taliban with a government that would not allow the country to be used, again, as an
al Qaeda base;*
2. To
enhance Canada's reputation in the world by doing a full and (more than) fair share in implementing the UNSC Resolutions on Afghanistan; and
3. To
help the Afghan people.
Items 1 and 2 are legitimate
vital interests, and would be for any country. Item 3 is not. It is something that is nice to do and it is a "supporting" role for 1 - it is easier to help the new government establish itself and take control if one helps the people, etc, but we (just like everyone from Australia to Zambia) have no vital interest in "helping" anyone else - it may be nice to do, people may like us more and they may even want to "help" us in return, but "helping" doesn't make it up to the
vital interest level.
Lord Palmerston, who may have been the best foreign minister of any country, any where, in any era, famously said:
"Nations have no permanent friends or allies, they only have permanent interests.” Our interests, especially our
vital interests matter: they, and they alone, are an acceptable reason to spend our treasure and the lives of our men and women in uniform on military operations. When we send people to fight and die we must understand "why." And that "why" must, always, equal "
vital interest." We must always try to have as few, very well understood, vital interests as we can manage - although we may find that we have too many and that some are too complex; that's one of the perils of power and, make no mistake, Canada has
some power and many interests, too.
Lord Palmerston
__________
* Remember, please, that Osama bin Laden had, specifically, named Canada (along with a very few (less than 10)) others as a prime target for attack; thus we had a legitimate need to defend ourselves.