Sometimes preaching morality is, as you'd expect, the moral thing to do. The English 19th anti-slavery movement affords an example. There is a clear and direct link from Josiah Wedgwood's moralising to England's abolition of slavery.
There's also useless moralizing. Many find it in the pronouncements of the UN, the West, or for that matter Russia on Syria. Condemning this or that, expressing outrage, is widely understood to have done no good at all. Some go further. They say the moralizing has actually made things worse, for instance by buying time for Assad. But I have yet to hear an explicit claim that, if the facts are as alleged, this moralizing is actually immoral. Why not? If a voluntary action makes things worse, what else can be said? Moralizing can indeed be immoral.
What then of moralizing about the FSA - I don't mean face-to-face criticism of wrong-doing, but a public dressing-down? Some of the most bitter opponents of Assad almost jump at the chance to condemn the only people who have any chance of stopping his atrocities. The FSA violates human rights! it executes people! it's brutal! it's 'dangerous'!
If the FSA were behaving like Assad - torturing the wounded in their hospital beds, mutilating and raping children, gouging out eyes, setting fire to living flesh - these condemnations would be welcome. Many resistance movements have matched the brutality of their enemies. Maybe moralizing about such atrocities would make things better, and could hardly make them worse. But that's not the current situation, and that's not what drives moralizing about the FSA.
Some people, of course, moralize about the FSA because they support Assad. But what about the opponents of Asad who moralize in the same vein? These people, in many cases, don't know what it is to make a choice in terrible times. Their moralizing isn't just some salutary moment of neutrality that shines a light on wrongdoing. It's a real choice with real effects. It can do more harm than good. If so, the choice to moralize is immoral.
There are abstract cases where neutrality is really neutral in its effects. I don't chose to support any Olympic team. So what? it would make no difference if I did. If I don't join in a game, it makes no difference as long as there are equally effective or ineffective people willing to play. But where Syria is concerned, any choice, if effective, helps one side or another. This includes the choice to express outrage over FSA human rights violations, and even more, to condemn or denigrate the FSA for these acts.
The FSA certainly does 'violate' human rights, and it certainly will continue to do so. Such violations are not necessarily even wrong, because the rights are not absolute. There is, contrary to popular belief, no great moral dilemma here. If I ' violate' your human right to free speech because failure to do so will in fact lead to a pogrom, that is not a Great Problem. It is right for me to do so, and actually wrong for me not to. Your right was never, in fact, violated; it simply did not extend to the situation.
The FSA is in desperate circumstances and in some cases, 'respecting' others' rights would actually be wrong, because the consequences would be as catastrophic as in the pogrom example. But there are also cases where the FSA could well afford to respect rights, and fails to do so, and an acts wrongly. Is it right to moralize about these cases?
No, not about the cases we know of, because that sort of thing will happen anyway. We know this from all past experience of desperate warfare. Only in some limited, gentlemanly conflicts such as occurred in 18th and 19th Century Europe were prisoners never shot out of hand, and all the niceties of human rights observed. In total war, in civil war, in virtually every other kind of war, you will get some out-of-hand killing. To say so is not to condone it, but to recognize the pointlessness of condemning it.
Highlighting the moral errors of the FSA isn't like preaching against slavery in 19th Century England. It can do no good but quite a bit of harm. A lot of fevered-hand-to-brow agonizing is circulating in newspapers and social media. "Oh, what a terrible choice, Asad or the brutal FSA. How our hopes have been betrayed!" Or a milder version: "The FSA is seriously fucking up. They don't realize what a terrible effect their excesses have on their image. They are losing their moral compass." These pronouncements are sometimes explicit, sometimes insinuated. Perhaps worst of all are the pseudo-calm, pseudo-balanced pronouncements on how 'both sides' have committed human rights violations and war crimes.
None of this can be proven to matter, but consider the effect it might have. Syrians, at home and abroad, as well as activists of other nationalities, experience stress, exhaustion, disappointment. They are bound to experience doubt - "are we doing the right thing? is this worth it after all? Are we blinding ourselves to the fact that both sides are, objectively speaking, pretty bad?" Add to this the decisions of those on the brink of choosing a side, or staying out of the conflict, and it's no stretch to suppose that the FSA is seriously weakened by the moralizing. The moral fastidiousness of those too naïve to realize what war is like would then be anything but moral. It would strengthen a really unusually evil régime against a resistance guilty of no more than ordinary military sins.
The damage done by moralizing about the FSA is an outcome that reasonable people, considering the consequences of their action, should expect. If they are high-minded, this isn't admirable. It is destructive of the desperate hopes of thousand so innocent people. Therefore, it is wrong.