As a decision made by a culture, it seems identical to me. Not that the enemy will desist because of their femaleness, but because we would be putting women in front to protect whoever is behind. And being women, like the Moslem "shields," they're not in much of a position to defend themselves, compared to the rest of the military being shielded by them.
All your caveats and requirements are well taken, of course, but the bottom line is that the whole point of a military, for all the reasons you cite, is to put the women and children out of harm's way. Otherwise, there's no point in having a nation at all. There's no excuse for its exercising authority over us if it won't do that.
When a people lose their child bearing age women, then they lose the ability to reproduce, that is why female life is so precious, not to mention that if Western man ever truly comes to see the weaker sex as nothing special and not due any special consideration, then we will have become savages, and the weaker sex would not like to actually see that goofy fantasy, be reality.
Might makes right, a sexually unaware warrior culture of ranking based purely on strength and successful aggression, would make women lowly indeed.
On what basis do you assert that putting women out of harm's way is the reason for a having a nation?
I am not sure what you mean by a "decision made by a culture" here.
If you mean that there is a Natural Law that says not to put women in harms way, and that both practices are in violation of it, then that is a plausible position.
But, your original comparison seemed to imply that there is not a more serious violation of Natural Law in using the reluctance of an enemy to hurt innocent civilians on either side as a weakness to be exploited. I hope you are not really meaning to imply that?