<<The reason that this seems far fetched, is that Canada has been allied or associated with the worlds most powerfull nations for generations , it would not seem far fetched in Uganda or Venezuela.>>
Both Canada and the U.S. are huge land masses of which an invading army can hold very little at any one time. For that reason, I believe both countries can make do with very small standing armies as long as the capability to rapidly increase them in an emergency is always present. IMHO, both countries, but the U.S. particularly, spend way more than necessary on the military.
The U.S. military in fact is not used for defence but to attack other countries all around the world. The cost of maintaining this capability and using it is draining desperately needed funds from Americans in need of help.