Cado said it for me -- which is good because I don't feel like typing much.
I don't think it matters if women are slightly less strong than men on average. Cause it's an averages thing. I am not a fighter, at least not physically speaking -- never have been, and I think many if not most women would be better recruits for the army than me. I know that women can excel in physical stuff. Otherwise the olympic games would have no women in them.
That said I disagree with women being taken in just because of gender politics. That's discrimination in their favour. If not enough women come to the army to make the army look progressive then maybe society should stop inculcating children to be a certain way from day 1, or maybe they should sort out their rape problem in the military, etc. A merely cosmetic change of a few extra % isn't really doing much for the world.