Game AI & net based machine learning

Hey, I've signed up on the site because of this thread. I find this stuff fascinating, but agree with the last 2 posts in that developing a general AI for games like Civ using machine learning isn't presently achievable. But, do you think it'd be possible to train an AI only for combat scenarios, and have the game use its deep learning derived algorithms only when it comes to warfare? I'm talking just moving units, attacking and defending, coming up with tactics to complete military objectives that a general, normal, preprogrammed AI sets. For example, the general AI sets the objective "I don't want to lose X city" and hands control of it's military (or a part of it) to the deep learning AI that's trained for warfare, in order to defend the city.