Quote Originally Posted by Ludens View Post
I used to do the same, but it may be something of an exploit. I suspect that the A.I. is programmed to march its armies at your cities, and when it can't reach a city (due to your fort blocking its path) it gets confused and gives up. It will only attack the fort itself when it has LOS on it. It's nice to have a docile A.I. for a change, but if my hypothesis is right, this will prevent "reasonable" wars as well as pointless ones.
Ludens:

What do you mean, the AI will only attack the fort when it has LOS on it? What's 'LOS'?