Originally Posted by
Aucald
The Orcs didn't have an actual enemy on Draenor - they were misled into thinking the Draenei opposed them when they didn't (by the Legion), who are the same beings that gave them the same Fel magic they eventually used to lay their world to waste and end up cannibalizing themselves before the Dark Portal gave them another opportunity to save themselves by attempting to claim Azeroth. So yeah, they were "victorious," albeit in a war founded on a lie and foisted on the idea that they'd then become the Legion's slaves (which they largely were when they invaded Azeroth). You can call that victory in the most technical way possible, sure; but in the end, they nearly damned themselves and even today they're still paying for their costly misjudgment.
You're conflating gameplay elements with established lore. Jaina was considered Antonidas' star pupil, and Antonidas himself is said to have believed that she "had the potential to become the greatest sorceress in human history." Similarly, Khadgar was also something of a prodigy in Dalaran and sent to Medivh to serve as his apprentice as the Kirin Tor felt Medivh would be unable to turn down someone as talented and incisive as young Khadgar.
Thrall was a gifted combatant long before he was a Shaman - he was trained as a gladiator by Sargeant and Blackmoore at Durnholde, and proved to be a "phenomenal fighter," with the natural savagery of an orc and the strategic intellect of a human. None of that really explains Thrall's natural talent for Shamanism, such that he quickly outstrips even Drek'thar in power, and is able to reconnect with the Spirit of the Wild despite bearing the Fel taint himself. Thrall learns and excels in Shamanism far quicker than either Jaina or Khadgar, who had been studying the Arcane for the majority of their lives up until that point. Thrall basically attains the power of an Archmage in a few months, as opposed to years of diligent study.
My idea of checks and balances is not investing a single fallible individual with autocratic power, and instead fragmented power among a group of individuals ideally representing the people they're meant to protect and serve. The Horde being shitty at this doesn't mean the Alliance excels at it, either. The creation of the position of High King was a definite step backward for the Alliance, ditto for Anduin's inability to stand up to his own advisors.
They got betrayed because of their own stupidity, or at least in Vol'jin's case because he was manipulated by outside forces. Durotan got betrayed because he allowed Gul'dan, the former leader of the Shadow Council that was puppeteering Blackhand, to continue to draw breath. Thrall put an idiot blowhard into the seat of power, said idiot proceeding to set the Horde against itself by being a power-hungry tyrant that surrounded himself with sycophants and yes-men. Vol'jin put Sylvanas into power, and Sylvanas turned out to be aligned with WoW's version of the Grim Reaper who wanted to kill everything and everyone to empower himself. So yes, they would've never won a war against the Alliance, because when ruled by a Warchief they swiftly become their own worst enemy.
Vol'jin also didn't appoint himself to any "supervisory" council - he was always part of the inner circle of advisors, and Thrall explicitly suggested that Garrosh listen to their counsel when making decisions. Something Garrosh swiftly discounted almost immediately on gaining power despite his own protestations of being unworthy and unready to lead. Similarly, Baine always suspected Garrosh was complicit in Cairne's death - even though he was wrong, it's understandable a cloud of suspicion would still surround Garrosh. Baine only had the word of Garrosh that Magatha was actually responsible. The Sha was too dangerous to deal with all on its own, and Garrosh proved that for himself at the Shrine of the Two Moons, when he infected his own troops with Sha energies that sent them into insane rages endangering his own people.
Garrosh was more than just an observer, especially since he spoke out volubly and set the basic tenor for the breakdown of the peace talks pretty much unilaterally. Garrosh and Varian were the only two individuals there too dumb to actually recognize an obvious set-up and did their level best to ensure that the talks were doomed to failure.
No one's really saying that Varian didn't have a pronounced anti-Horde bias, either. Rather, he had a significant one he never really tried to hide. Part of that was down to his own unstable nature due to what had been done to him what with the whole splitting him in half thing, and part of that was just down to the memories of his treatment as a Horde gladiator slave. Needless to say, he was quite opposed to listening to reason.
Again, I didn't say I agreed with Baine's rationale on the war, only his stance on Taurajo and the greater notion of the conflict being another in the endless and self-perpetuating cycle the Horde and Alliance were involved in. Even a broken clock is right twice a day.
A realistic Alliance would've wiped out the Horde when it invaded Azeroth in the First and Second Wars after they had been roundly defeated, as opposed to putting them into internment. That being said, the Third War basically showed the value of the two main factions working together - if they hadn't joined forces, we know the combined Scourge and Legion forces would've been victorious in the end.
And they didn't know at the Wrathgate incident that Putress' forces weren't there on behalf of the Horde, either. They had only Sylvanas' word that she was responsible for it and that Putress was attempting a coup on her in the process. Hell, that plot itself remains murky even to this day - as there's been evidence that Sylvanas always had Putress' actions in mind and only used him as a shield of plausible deniability for herself. The Alliance was wrong, but the stance itself was still reasoned well enough, they just didn't have all the facts of the matter (and likely never will).