The total population of European NATO countries is 520 millions. Canada's population is 40 millions. The idea that Canada is and should be an important provider of land troops to Europe is ridiculous. At the same time, Canada has little need for land troops to keep invaders from Canadian soil (unless those invaders are Americans,
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Canada's contribution to European security should come in two forms: As an arsenal of freedom, i.e. as an industrial base for producing what Europe needs to fight, and as a provider of the delivery of these products, which means a strong Navy supported by Air Forces. Coincidentally, strong naval forces supported by air forces are the things required for Canada's own self defense. Since it also contributes directly to the protection of main land USA, it also constitutes a fulfillment of our continental defense obligations.
For us, 2% buys more than what we need if, and only if, we spend it on naval and air forces - regardless of the Army's constant badgering that we need to make them capable of going to a fight in Europe.
Funny enough, concentrating on Air forces and Naval forces was the plan of William Lyon Mackenzie King in WWII and it is only the fact that all European powers dissolved before Germany, except the UK, that forced his hand into building up the army too.