How can Theramore be the first act of war when it was the transition between Cata and MoP and the war started in Cata?
It wasn't Pandaren artifact, it wasn't kept by Pandaren, it wasn't hidden by Pandaren. There's nothing Pandaren about it. And it was recovered by the Night Elves, so even if there was any stealing from the Pandaren it would be by the Night Elves. Also, Jaina aided the Night Elves in safeguarding it against the Horde. By using magical traps to imprison or kill Horde members. After she became "neutral" as the leader of the Kirin Tor.
She helped them a lot and then invaded their core territory. And Horde doing anything to the rest of the Alliance is rather irrelevant to whether or not they betrayed Jaina.
The only Alliance outpost in the Barrens prior to the Cataclysm was Bael'dun and even that was Alliance intruding on Horde territory. What @
Kangodo was talking about was Jaina's troops spreading all over Horde heartlands and attacking shit. Before Theramore.
Irrelevant. She broke neutrality by aiding the Night Elves. And using Vol'jin as an argument is you shooting yourself in the foot. Regardless of his differences with Garrosh (and by "differences" I mean surviving an assassination attempt), Vol'jin was in favor of Garrosh getting the Divine Bell over the Alliance.
There is no point of view in which the Horde attacking Theramore after Theramore's troops spread across most important Horde zones like a locust swarm and planned to invade even Orgrimmar itself is not a betrayal. It's logical consequence of events that Jaina brought upon herself.