I've always said the service needs to be very careful about playing the stop-loss card, i.e. they need to be very sure that they actually "need" stop-loss to continue combat ops, not just to hide the glaring holes in their personnel policies.
A couple of big questions come to mind: 1) Would the "war on terrorism" be possible while allowing a more or less "normal" flow of attrition out of the service and newguy training into it, perhaps targeting only highly "critical" specialties for stop-loss, and 2) Could the government/military present a convincing case for the "constitutionality" of stop-loss, if some of the affected groups ever managed to band together and present some sort of "class action suit?"
After all, there is no draft. One can make a case that you cannot be "forced to fight" simply because you happen to be in the service when hostilities begin, while others sit comfortably back at home out of harm's way. There is an assumption, in the "all volunteer force," that you are volunteering for combat duty as well, but there is also the assumption that you can, at some point, decide that you're NOT a volunteer any more, right?
Also, last time I checked, flying was a "voluntary" specialty. All you have to do to be removed from flying status is to request it. Certainly don't want folks flying multi-gazillion-dollar planes who don't really want to do it, right? So, how "critical" is your specialty to the Air Force if you decide you've "lost the edge" and toss those wings on the table? How does the Air Force justify keeping an EX-pilot on stop-loss, when they are letting the medical specialists (who are also pretty critically undermanned across the board) leave?
Now, probably, it would never come to this kind of "labor/legal action" scenario, since military pilots are generally patriotic enough and concerned enough about how they are "viewed" that they'll probably just salute smartly and fly on, rather than risk undertaking some sort of "distasteful" court battle that might make them "look bad" even if they won (which I suspect they would, "freedom" being what it is).
But if I was the Air Force, I'd be very careful about how I used a "manning tool" that is only marginally constitutional at best, difficult to defend in the face of the almost total lack of the use of other tools such as selective service and formal declarations of war. Just how do you tell an American citizen that he must remain in what amounts to "conscripted service" beyond his agreed-upon commitment, when you allow his fellow servicemen to leave? Might take a few years to get there, but I'll bet the Supreme Court would have a field day with it
Wiser to save such a tool for a "real" war, instead of using it every time you get caught with your pants down for not having a clue how to manage the rated force.
