Why ARE men the only gender who gives a shit about their country? I guess it goes back to pre-modern rape and pillaging. If a male loses his territory, he's killed no questions asked. The women in the territory are raped and made mothers by the conquerors where they are allowed a second chance at life, thus survival-wise there were 0 consequences for losing her territory since she can still live and continue reproducing with the new male in the new territory.
But again for a man? He's just fucking killed so he NEEDS to care because losing isn't an option.