Distraction vs. Discrimination

I just read that Santorum opposes legislation that is about to pass allowing women to serve on the military front lines. He claims that because men tend to be protective of women, they would worry about the women and be distracted from doing their own jobs. This made sense to me.

Then I read the handful of comments that were showing at the bottom of the page. One of them mentioned that soldiers are already concerned about the men they serve with and manage to get their jobs done, so why should adding women change that? This also made sense.

So, in a very dangerous situation, would a man be significantly more concerned about the welfare of a woman than he would that of a man in the same situation, assuming both to be strong, healthy, fit, and competent? Having never been (a) male or (b) working with others to accomplish an important goal in life-threatening conditions, I find this impossible to answer.