This makes sense if you focus on a few things:
- there are some costs savings, minor as they may be, by opting out of NATO efforts such as the AWACS planes, AGS (alliance ground surveillance [drones]), etc.
- the Harper government would seek to undo any and all Liberal legacies that they can find. NATO happens to be one of those things that the Liberals always engaged.
- the general Harper distaste for anything that is multilateral. There is a definite preference for bilateralism.
- as it wastes whatever street cred Canada earned in Kandahar. If Canada gained heft in Brussels as a burden bearer, then withdrawing means that heft goes unused as hard as it is to measure heft.
- if the Arctic is Canada's defence priority, most of the countries involved are either NATO countries (US, Norway, Denmark) or NATO's raison d'etre (Russia). One would think that as Canada tussles with Russia over their respective expansive claims that Canada might want more than just the US. Sure, bilateral relations with the US plus NORAD help tie the US to Canada, but NATO and Article V would be an additional bond.
And then there is Ukraine. Stephen Harper and Foreign Minister Baird have come out swinging, demanding more action and more support for Ukraine. Why? The Russian menace? The threat to Alaska? The political relevance of the Ukrainian Canadian community? I'd have to bet just a bit on the latter given my career focus on ethnic ties.
So, what happens if NATO wants to do something about Ukraine? Would disengaged Canada set aside or would enraged Harper/Baird jump in? If this was someplace else (Syria?), I would say the former, but the political relevance of Ukraine for Canada might just tip the balance. As a social scientist, I am kind of thrilled to see the natural experiment play out. As a person who does not want World War III over Ukraine, I am just a bit nervous.
I don't think there is much NATO can do about Ukraine. Especially since it will be mighty hard to get consensus, which is necessary for NATO to act. So, perhaps this is all performance art by Harper and Baird since action is hardly likely.