For the forseeable future, military opponents of the US will be failed states and societies. These will have little likelihood of following any sort of restraint or conventions in war. This means that captured female soldiers will almost certainly endure much harsher treatment than male soldiers and there is little or nothing the US can do to discourage that kind of behavior.
In addition there is the reaction of others to a woman in peril. The resuce of Lynch is apparently one of two such rescues rescues since WWII (the other a SpecOps raid in Panama in 1998 during the US invasion). It was a big operation involving a diversionary attack and a four hour gun battle at the hospital. I do not object to this — I think it's wonderful. But that is precisely the problem. If women are to accepted for combat positions we will have to, as a society, become more callous toward this kind of harm when it is inflicted on women. Given all the effort that feminists have spent trying to encourage that kind of reticence it's a bit strange that women in combat is also a goal.
In summary, I don't know what is best in this case. It's hard to say “you can't do this because you're a woman” but on the other gender is not a purely social construct and sometimes we just have to accept that.
I was discussing this with my co-worker BBB and She Who Is Perfect In All Ways. BBB suggested that perhaps we should have gender segregated combat units (say at the company level) to get around the mixed-gender problems. SWIPIAW didn't think it would work — “then who would open the jars?”