Fighting close to home is a lot more fun, take it from me.
But is not always possible, viable, and/or desirable.
BattleMaster isn't a game of mindless fighting. There are games like Risk! and War Islands for that.
Unrest due to lame war is important enough for leaders to take into consideration. If we intentionally sabotage long-distance wars in the game design, then we are just contributing to making those who participate in them have less fun than they otherwise would have.
