I'm not sure that I agree. I guess it depends on what you mean by "win". If you mean win that particular engagement, sure. But if by "win" you mean accomplish the objective, which in this case included not having the local population hate you for obliterating their city, then I don't think it's a luxury nor do I think you can win without such considerations. And really, I'm not sure that it's fair to say that the US has "won" either of the two major asymmetric wars it's been engaged in for the last 17 years, even with all of the political constraints they've ostensibly tried to follow.
The decay and destruction of their infrastructure was basically a foregone conclusion when we started the wars. Without our intervention and continued presence the damage would have been much higher. This in no way excuses or justifies us starting the conflicts to begin with, but, our rules of engagement are very strict and err heavily in favor of preventing civilian casualties, too a fault, many soldiers would say. This also means minimizing. Look at the battle of Ramadi. We /definitely/ won there. Then we lost it, and won it back. So it is quite possible to win these wars, but they require advanced warfare skills at a tactical and strategical level and the political will to not back out. We only last Ramadi because of politics.
Politics, in the large sense, is also the only relevant actor in a conflict: the military victory at Ramadi (either one) was rather inconsequential for the larger goal of bringing peace.
