If there were a war, which would probably be started some way or another by the Von Helsons, we wouldn't have a Barton Town anymore. They don't have the man power, nor any stratigic location to fend off any sort of an attack. After that, I think Isle de Gambino would be the next to loose power, currently. It's got a supurb location, but what good is that if it has no other defences? Gambino is down and out, he's got no power anymore. if the Isle was to receive attack, there wouldn't be anything he could do about it. I think Aekea would cause the most problems for anyone. It's far out of the borders of Barton, and it's got the steepest, rockiest terren of any city. Also, it looks as if it is either on a hill, or in a ditch. If it were on a hill, well there's another advantage. If it were in a dtch...well...I guess it could prove useful in someway. Also Aekea has Liam who makes robots. Robots are the best soldiers becuase they can kill without compassion. Liam may have a "dating problem" but that's nothing compaired to what else he's capable of.
And if the war were not started by thr VonHelsons, then Durem has a pretty good advantage, given what it's made of. Store is good, but other then that, the town seems to be more based on decorative looks than any sort of defence.
I honestly think Aekea has the greatest advantage if there were to be any sort of war.