Whether or not you're the one doing the lying, it seems pretty clear to me, from everything I know IC and OOC, that at least a big chunk of Caerwyn's justification for the war was false. People tend to get upset when that sort of thing happens. I know I'd be upset if, for instance, Morek Empire had declared war on Pian en Luries, insisting that we had planned to attack them next.
Isn't that not really in the spirit of the game. Sure Alanna would be pissed if Morek did that but you shouldn't really mind. It would actually be kind of cool.