Re: How to deal with invasions?
As far as I've experienced yes, it is normal that the AI do not consider "invasion" as a special event.
With MOS you can have Tol Acharns and counter invasions which have been created for the player to give some relief and defense against AI launched invasion. Althought I read more than one time around the forums that thecnically speaking the AI allied good factions might use counter invasions to help each other, it never happened in my games till now (but I haven't played Gondor/Arnor/Rohan with MOS yet).
Hope it helps, my suggestion is not to rely on allies to face invasions 
Flinn
Last edited by Flinn; January 22, 2013 at 09:26 AM.
Reason: mispel