@Blayze
The Horde (read: the Orcs) are not attacking Alliance because they see a threat. They are attacking Alliance because the Alliance have something shiny to take. And because you aren't a real Orc warrior unless you fight and kill people as often as possible, preferebly all the time, preferebly PREFEREBLY by charging straight forward into their ranks.
And victory after victory for the Horde is happening because the people that wear Horde t-shirts and yell "For the Horde!" at every opportunity wants it to be so.

@wizlynjonstar
The Alliance IS awake. It's defending against the Horde everywhere. And even in some cases attacking. And in every region ultimately losing. Because they are weaker. And waste their numbers fighting other enemies which only makes it easier for the Horde to wipe them all out.
Oh and why do people expect that Blizzard will give the Alliance any kind of victory against the Mighty Horde? Seriously? When did Blizzard give any official statement that that will EVER happen?
All we've read/heard is this.
1. Theramore will burn.
2. It will always be unfair.
3. It will get a lot worse for the Alliance.
4. Varian will become the new High King. Alliance will need him because things will be so bad for them in the future. (Meaning things aren't so bad right now, compared to how they will be.)
5. The Alliance Battlecry should be "have mercy", "we're trying" or "not the face".
6. Chris Metzen's hands burned when he was wearing an Alliance t-shirt (and he was only wearing it as a prank).
7. Maybe we should give the Alliance a nice symbol?
8. For the Horde!!! (repeated a million times from Blizzard management each Blizzcon)

What we have NEVER read/heard (but people keep thinking Blizzard is meaning anyway):
1. Things will get bad for the Horde.
2. The Alliance will take something from the Horde that they value.
3. For the Alliance!!! (by any Blizzard manager or spokesperson that will not say For the Horde! before or after that).

Seriously, how hard can it be to connect the two facts a) Blizzard loves the Horde much more (as evident by ANYONE that has ever been at Blizzcon or seen it streamed) and b) the Horde is winning everywhere and is much stronger, cooler, mightier and made of awesome?

It's not exactly rocket science. ;-)