I began playing this game about a month ago; I'm not new to this type of game so the principles were familiar, just the details varied.
Shortly after I began this whole "war" thing erupted, and I've been trying to keep up with all the various postings discussing it. I have no opinion on the war itself, but I think there are a few things to think about.
1. Illy is an "open-ended" game. There is no final "winner" to end the game and start a new one. This means that early-starting players will always have significantly more power than newcomers. Yes, I know there's a 10-city limit for each account, but to a new player like myself that seems like an eternity away.
2. The game mechanics currently allow the most powerful players to arbitrarily attack much weaker ones. Whether this is acceptable within the game is not for me to judge, but if it becomes common practice then newcomers will probably leave quickly when they see that progress may be impossible.
I happen to be a highly-ranked tournament bridge player in real life. Decades ago bridge suffered the same problem; new players were reluctant to play in tournaments because they had no choice but to compete against much better players, and would almost always lose. Attending tournaments is expensive, so new players stopped attending and tournaments began to wither and die.
The solution adopted by bridge's governing body in North America was to stratify games. Players only compete against others of similar expertise (as measured by masterpoints won in games). As players gained more masterpoints, they have to move to a higher bracket. At all times, lower ranked players have the option of playing against higher ranked players if they want to, but higher-ranked players can never choose to compete against lower-ranked ones.
Perhaps Illy needs a similar system. Players could be placed into "brackets" based on some simple criterion such as Overall Rank. Players would be free to pursue their own interests, but would automatically be pushed up into higher brackets as they progressed and new players joined at the bottom.
As far as non-consensual military attacks go, the game might only allow a player to attack someone in their own bracket or higher. Obviously it would need to be programmed to be more complex; alliances would have to be considered, along with considering a group of lower-ranked players "ganging up" to attack one higher-ranked. I'll leave all that to the devs; I'm sure they can figure it out and the devil is really in the details. Basically I'm saying that non-consensual military actions should demand some sort of level playing field to start with (unless a lower-ranking player chooses to waive that condition); then the players involved can use all the strategy, tactics, diplomacy and tricks they can think of to win.
The danger to the game is that it is being advertised as one in which players can pursue their own interests; occasional setbacks are fine and necessary to maintain interest, but the possibility of essentially being wiped out probably isn't. That advertising seems to me to be more misleading as time goes on. If it's going to be purely or largely a military game, then advertise it as such. But please don't mislead new players by pretending that it's something it isn't.