Funny, I remember them waiting for 10k years for the return of the Legion. If they were stupid agressive they'd have built a larger army and opened a new portal to demon land.
Plus, they have thousands of years of experience fighting satyr, silithids etc.
---------- Post added 2012-11-09 at 12:22 PM ----------
As a night elf, I can say that is a great idea. Nothing can go wrong with blowing up the world! But, for now, we'll limit ourselves to Pandaria. I mean, just think about it, we get rid of the sha, of the mogu and the pandaren together! So, who's with me?