The moral principle that women should be saved out of the harms way in wars and other emergencies is probably as old as humanity itself (though it has often been applied only to "real human women and children", in other words, to the ingroup). It's without doubt among the most important moral principles. At the same time, it probably gets discussed less than other important moral principles because it sounds improper nowadays. Perhaps we take it for granted but pretend that it doesn't exist.

Less than 50 years ago people who led the world - and were mostly men - didn't have any such qualms. They acknowledged that it's self-evidently an important principle and that it should be followed better. They also wanted to make it universal so that also outgroup women should be protected.

Declaration on the Protection of Women and Children in Emergency and Armed Conflict by the United Nations:

5) All forms of repression and cruel and inhuman treatment of women and children, including imprisonment, torture, shooting, mass arrests, collective punishment, destruction of dwellings and forcible eviction, committed by belligerents in the course of military operations or in occupied territories shall be considered criminal.

6) Women and children belonging to the civilian population and finding themselves in circumstances of emergency and armed conflict in the struggle for peace, self-determination, national liberation and independence, or who live in occupied territories, shall not be deprived of shelter, food, medical aid or other inalienable rights...

https://www.un.org/en/genocideprevention/documents/atrocity-crimes/Doc.19_declaration%20protection%20women%20armed%20conflict.pdf

The Istanbul treaty proves that the principle hasn't gone anywhere. The difference is that they made up all kind of "evidence" to "prove" that violence against women is a much more pressing problem than violence against men. In other words, they pretended that there was a rational reason to protect just women. But actually it's the same old chivalry in new clothes. Or not quite exactly the same: they have pretty much dropped the children from the "women and children first". That's, I suppose, feminism.