How a military draft could be legitimate (written in late 1970s)

I just typed this up to post on Facebook, responding to one of my former students who wrote an op-ed calling for reintroduction of military conscription in the U.S.  It is taken from the instructor's manual to my 1981 college textbook,  and I had to type it because the textbook and the manual were written before I could do computer editing.

"In the instructor's manual for my 1981 college textbook, I commented on how a LEGITIMATE draft could be done: Noting that conscription has always been "selective," I noted that "A less obvious alternative, for a truly colossal emergency, might be general or UNselective conscription. EVERYBODY, literally, would be drafted at the same moment---men, women, children, with no exceptions whatever. Thus THIS conscription could be accomplished by government-as-legislator rather than by government-as-bandit .... 

"Each person would then be subject to serving where ordered to do so. Young children would probably be ordered to continue playing or going to school. 'They also serve who only sit and wait.' Many people would be ordered to perform--perhaps continue performing--productive roles in farms, factories, and mines. 

"One startling aspect of such a total draft would be that people already IN the armed forces would also have to be drafted. No exceptions means NO exceptions! Thus generals and admirals would be drafted. The enthusiasm of such professional officers (as well as congressmen and other top government officials) at being drafted might be minimal because of another feature of this draft. Since a draft is based on repudiation of the market (during the emergency) as a means of raising and allocating manpower, all draftees must receive exactly the same compensation (cash plus fringes) while the emergency continues. The impossibility of providing everybody with an admiral's standard of living is self-evident; hence admirals will have to live like privates while the draft remains in effect. Of course the top brass, military and civilian, are all very patriotic and would undoubtedly be willing to sacrifice for the national welfare if necessary. But they might be somewhat more conservative in their willingness to decide that an emergency exists."