Considering we didn't do that, that's obviously not the case...
Edit: Besides, why would we do that? We have the most powerful realm on the continent on our side. 
Most defensible, not most powerful. Significant difference. Especially with the new estate/tax system. Didn't a bunch of Sirion's regions suddenly become much less profitable?
In truth, all it'd take is a duke (or the lords of several key regions) seceding or joining a neighboring realm and suddenly Sirion has a huge gap in its armor.
It's funny though, for as much as Sirion tries to portray others as evil/dishonorable, they seem to forget that the ganged-up war against them was due to them trying to sell out other realms (including Westmoor) out to Fontan.
...but I'm sure there was no legitimate reason for realms declaring war on Sirion when it was betraying its allies.
