Is Military manditory?

In both Canada and India military service is not required and if they did then it could create some problems during world war. Because both India and Canada have been colonized by the French and the English and there arises the question of which countries army should I help. Luckily military service is voluntary and I think that is the way it should be. I feel that if you want to be part of the military then go ahead but if you don't want to risk your life, then you should not be forced to. The only possible reason I would want to join the military is if there is some extreme requirement by my country.