Board Thread:Warhammer 40k General Discussion/@comment-7699236-20150618150629/@comment-26436507-20150623161040

That's an unreasonable comparison really as the sisters of battle is indeed a all female unit, albeit with some male additional ranks. The background material is geared that way and it is meant to be a all female organisation as a result of it's evolution in the fictional time line. Otherwise it would be something along the lines of the 'family of battle' if it had males and females. The sisters of battles identity is so derived and that's why it's females only.

There isn't such a artificial barrier on female marines if games workshop so desired it. As already suggested by another poster it is likely the Emperor had the capability but not the want to create female marines. The space marines are meant to be the pinnacle of humanities defenders, that is there identity. Both males and females could do that.

Does it really matter? No it doesn't but it might help if there were some genuinely interesting female characters for female (and so inclined male) fans to be appealed by. It's also good to subtlety challenge latent sexism of some enthusiasts along the way.