In 2007, John Piper wrote an article in World Magazine called "Combat and Cowardice." It is worth reading as we attempt to think Christianly about all of life, including women in combat. Here is the introduction:
If I were the last man on the planet to think so, I would want the honor of saying that no woman should go before me into combat to defend my country. A man who endorses women in combat is not pro-woman; he's a wimp. He should be ashamed. For most of history, in most cultures, he would have been utterly scorned as a coward to promote such an idea. Part of the meaning of manhood as God created us is the sense of responsibility for the safety and welfare of our women.