USA isn't defending Canada against any threat so have fun trying to be the world police to justify your bloated military wasting tax payers money.
Canadian national defense, like the rest of NATO, is subsidized and paid for by the USA. Peace and stability in Canada is 100% built on the USA being "World Police" and ensuring no dictator or aggressive nation decided to annex said Canada. *** yourself all you want, history is replete with aggressive nations deciding they need "room to grow" and grabing land from their neighbors. In fact I think most of World History is exactly that.
https://en.wikipedia.org/wiki/Canadian_Armed_Forces
Canadian military is .. get this ... 68K with 32K in "reserve".
Size of US Military is 1.2 million with another 811K in "reserve".
And then we got all the expensive weapons platforms including the floating cities and mobile operating bases that are modern aircraft carriers.
The USA could easily cut it's defense by two thirds and have a sufficient ability to guarantee national defense, it just couldn't guarantee the national defense of the other NATO members or do much of anything else. Many Americans, including myself, want this to happen, dissolve NATO and let all the other countries in the world fend for themselves.