As far as women in combat go, I know I would not have been able to meet the physical requirements when I was 18-20 years old, not that I had any interest in military service. There are a few women who probably could-women are bigger than they used to be. I'm 5'10", which I always thought was tall for a woman. Then I moved to Detroit.
I know a lot of the issues in physical abilities has to do with upper body strength, though, and even a women who is 6 feet + tall might not have the same level of strength that a man of the same height would have. Then again, she might-watch Venus Williams when she's having a good match. She serves like a man.
As far as vulnerability to rape is concerned: if you are talking rape by the enemy in combat or as a pow, men are as vulnerable to rape as women are. As far as rape by their male peers, I have a major problem with blaming that on the nearness of females, and not on the violent impulses of men who should be in control of their impulses. It cuts very close to the way that Islamists view women-put them in burkas so men won't be tempted by them.
Living in the world of Shoulda instead of actual Reality has gotten countless people killed. Military combat operations, the outcome of which actually matter to a Nation for more macro reasons than the mere opportunity for the people involved to increase their self-esteem, self-actualize, earn benefits, and all the other societal and individual freight that weighs ours down now, is not the most suitable place to experience an epiphany about the difference.