Not to agree / disagree, as I am not an expert.
I think most police in Canada are unionized. Police , like any other emploees , can't be drafted , and can quit anytime.
But , wouldn't it be different for the CAF in that , although it hasn't happened since 1945, there may come a time "during hostilities or during a time of war as declared by the Government of Canada" when civilians are drafted into the CAF.
When, like it or not, Reservists are involuntarily activated to full-time and, like it or not, may be sent out of Canada.
VR's will / may be put on hold until "cessation of hostilities".
If that is how it would work?
What good will a union do then?