Kul Tiras is the greatest naval power in Azeroth, and a former ally. But we've had little contact with them since Jaina's father, Lord Admiral Daelin Proudmoore, was defeated at Theramore.
Many have criticized Jaina's decision that day, saying she believed so deeply in the promise of peace between the Alliance and Horde that she betrayed her own father.
Perhaps she feels the time has come to atone for this.
Loath as I am to put Jaina in harm's way... Kul Tiras must join the Alliance.