While in the past I have been a proponent of allowing inter-realm warfare, I tend to agree with Indirik about team play, which I am increasingly convinced is important to maintaining the game.
You are still part of a team, just a much smaller team, IE your Duchy. From time to time your team might ally with other teams in the realm, or not. Its not like we don't have intrigues and arguments between duchies now, just they can't be resolved in a military fashion without one or other succeeding.
