At the proverbial end of the day, the moral engine of the argument for President Obama's action is that, in the United States, we do what is necessary to bring our soldiers home. See, e.g., David Brooks's piece today in the NYT.
I agree with this. Sgt. Bowe is/was an American soldier. He was almost certainly a deserter, although under what circumstances remains in some doubt. He might conceivably have been a collaborator, although much of the evidence being used to make that argument derives from his actions while with the Taliban. Without knowing more about whether he was their comrade or their captive, such evidence is so inherently unreliable that it must be discounted.
So, yes, he was an American soldier, and for that reason alone was worth bringing home no matter what else he is, including a deserter or worse than that.
Where Obama and his apologists err is in thinking that this ends the argument.
First, there is the question of when he was to be brought home. When a war ends, each side generally repatriates enemy soldiers it has captured. But this war is not over. Thus, even assuming that Bergdahl was a captive and not a collaborator, extraordinary efforts to bring him home right now need an explanation.
The initial explanation was that his life was in imminent danger, but that has all but faded off the screen. A "proof-of-life" video shot in December apparently showed Bergdahl in poor condition, but (1) that was six months ago and (2) even those sympathetic to Obama's position have not claimed that it showed a man at, or near, death's doorstep. Anyone living off the land in the mountains of Afghanistan for years is likely to look less than robustly healthy.
An accompanying explanation has been that a "window of opportunity opened,' and had to be acted upon immediately. But this is just so much ipse dixit. It now comes out that our "we-don't-negotiate-with-terrorists" Administration had been negotiating with them in 2011 and 2012, and advised Congress of this fact. (This is also being dragged in, as an obvious back-and-fill afterthought, to assert that Congress was given the legally required notice after all). There is simply no plausible explanation supporting the now-or-never theory.
But even putting all this to one side, there remains the central question. Assuming arguendo, as I do, that we do everything we can to bring home our own, what exactly does "everything we can" mean?
Suppose the Taliban had demanded that we torture ten children or they would shoot Bergdahl in the head that very day? Would we do it? Suppose they had demanded that we kill one of the five commanders we held at Gitmo -- say, one not in favor with the Taliban regime currently in power -- and that we do it without trial or any legal process. Would we do that?
Of course we would do neither. The claim by David Brooks et al. that the price of the Bergdahl deal didn't matter is arrant nonsense. Indeed, it's truly astounding stupidity to say that the price you pay for X doesn't matter, simply because X is a moral imperative. The world is chock full of moral imperatives, and when confronted with a choice among them, you actually have to understand it is a choice.
It's impossible to believe that either Brooks or Obama fails to understand this. Thus their dismissal of, among other things, the very real prospect that the released Taliban commanders will kill more Americans, and/or that agreeing to this deal will incentivize stepped-up efforts to take Americans hostage world-wide, is as logically bankrupt as it is morally deaf.