Indeed. TMP and Dwilight just can't go together in my opinion.
Yet. Realms just need to mature a bit more and things will settle down.
The main reason we're not fighting is because our capitals are right next to each other over a sea route. Sure, either side could throw men against the walls, but the other side would win spectacularly and then march on their enemy's capital whilst the others limp home. It's pretty stalemated and soldiers find that boring, they want their rulers to do something about it
now. It'll all be solved when Madina or Aurvandil get siege engines and dare to attack, which will be soon.