Any ideas of Canada being invaded are utterly ridiculous, we're strong allies with the country that has by far the strongest military in the world. Nobody outside the US has the power to project force at a large level (Even poor countries with awful militaries like iraq and afghanistan still present serious problems years on). Even without US military backing it would be virtually impossible for a nation to get enough troops, supplies, equiptment and logistics over here to actually occupy us and 'take our resources' from us. With US military support, the idea of anyone invading Canada is laughable. Aren't you big military folks supposed to know your stuff?
The stuff about a larger military required to retaliate for hypothetical state-sponsored terror attacks on Canada, by enemies we don't have is ridiculous.
Canada's military should at most remain the smallish professional force it is today, and adapt according to changes in its requirements.