idjit
Chieftain
I am starting to lean towards something like this as an explanation - they aren't really threatening you "for realsies" but they are making sure you at least keep up some kind of military or something. But then again, they way the AI just burns through city states makes me lean back so, yeah lol7. When the AI declares war, it seems to be a "just kidding" war. There's an initial rush of a few units, but no follow-up. The AI seems to "forget" that it declared war and is just waiting to be punished.