I missed the thread you referred to, so let me have a go at it. I respectfully and strongly disagree with your last statement.
It is actually two statements in one. There is a difference between self-defense and the defense of others. So lets look at each one:
Self-defense - this is a moral right, but not an obligation. The right does not exist on one’s gender, BUT it is certainly NOT the root of the Church’s teachings on warfare. So it really has not bearing on the matter.
The protection of others:
Here, you are closer to the truth. It can definitely be considered the root of the Church’s teachings on warfare. So far so good. But, let us look at what the Church says specifically:
It can be an obligation for one who is responsible for the lives of others. Therefore, your statement that it is not based on gender is only valid if (and only if) you can show that women (in general) are responsible for the lives of the community at large. You have not shown that. For sure, when women join the military, they become responsible, but are they responsible for the lives of the community at large when they are not in the military? A long term view of history, spanning almost all cultures, would indicate they are not.
-If self-defense and the protection of others is not the root of Catholic theology on warfare what exactly is?
-While you need me to show that my argument is valid, you have failed to show the validity of your own in regards to men being responsible for the safety of the community.
-History actually argues against your argument since the women, not the men, were the ones left to defend “hearth and home” while the men were out hunting, exploring, trading, or waging war on others. Frankly, if we view the development of warfare and the historic gender roles in it through the lens of Catholic theology concerning war (only in defense, as a last resort) we will find that women, not men, are the ones that have historically been given the responsibility of safeguarding the community.
-Sociology also argues against your argument, and for mine, since women are found in almost every culture to be the ones responsible for the home and well being of the community.
-Nature itself (biology a better word? not to be confused with Natural law) also argues against your argument and for mine. One never hears the phrase “Don’t get between a father bear and his cubs.” We also have the situation in which most animal species that have something we can label as “community” are structured in such a way that most of the males of that species don’t actually live within that “community.” Most of the populations of those “communities” are females (adult and juvenile), juvenile males, and one to a handful of adult males.
-Lastly, we have the case of St. Joan of Arc, who was given a mission by God to engage in warfare with the English. We are left with only three options- your argument is flawed, St. Joan wasn’t on a mission from God (the Church says she was), or God violated natural law (not possible).