Jonsey, you missed the point on car insurance entirely.
As for why do we need tanks (I agree with the comments on Hillier, frankly, and if Canada has decided it wants out of the heavy armour game, then go the whole hog as we appear to be doing) - the point has been made by recce41 that we may one day need them (insurance, right?) and if that day comes after 20 years of not having them, we will have lost all the hard earned experience passed down from Radley-Walters and that ilk who learned the hard way at the hands of Panzer Lehr, Hitlerjugend, Leibstandarte Adolf Hitler, et al in Normandy and beyond - and the successive generations who learned at their feet, and passed on to their successors, etc.
However, if we have finally decided that having allies means depending on them for some things (like armour and the big stick!) while specializing in other areas (light armour, peacekeeping and other peace missions), then so be it. Do it all the way and forget about airlift, tanks, and other expensive stuff we won‘t need as long as we have friends with big sticks - and can keep paying the price of being their allies. Softwood, gas, water etc.