Why does Sauron (in the movieverse) attack Erebor instead of, say Gondor or the Woodland Realm? [closed]

Question

Wouldn't attacking the Woodland realm, a surprise attack on Gondor or maybe even sending these legions of orcs, led by the witch king to Angmar be more beneficial than an attack upon the Lonely?

Why does this make sense tactically?

Answer 1

First of all, not having regained his full strength does not necessarily make Sauron weak. Even at 50% strength, or even 25%, Sauron is still one of the post powerful beings in Middle-earth.

There's actually no evidence in the movies that Sauron has any interest in Erebor at all. The scene between Azog and the Necromancer runs thus:

AZOG: What of Oakenshield?
NECROMANCER: War is coming.
AZOG: You promised me his head.
NECROMANCER: Death will come to all.

Following this Sauron departs and Azog assigns the task of dealing with the Dwarves to Bolg, apparently of his own volition.

Although you're asking specifically about the movies, in the books it's made clear that one of Sauron's primary interests in Erebor was to ally with and then use the Dragon, Smaug. This is made most clear by Appendix A of Return of the King (and is therefore material that Jackson is allowed use), describing Gandalf:

Among many cares he was troubled in mind by the perilous state of the North; because he knew then already that Sauron was plotting war, and intended, as soon as he felt strong enough, to attack Rivendell. But to resist any attempt from the East to regain the lands of Angmar and the northern passes in the mountains there were now only the Dwarves of the Iron Hills. And beyond them lay the desolation of the Dragon. The Dragon Sauron might use with terrible effect. How then could the end of Smaug be achieved?

Dragons are not neutral beings but were created by and served the first Dark Lord, Morgoth, in the First Age. A Dragon would naturally be expected to ally with Sauron, so hence Sauron's interest in preventing the Dwarves from retaking Erebor.

This also makes it clear that Sauron's original intent was to attack Rivendell. As a primary stronghold of High-elves, he doubtless saw it as a more strategic and beneficial target to destroy.

Of course in the book Sauron is not even remotely involved in the Battle of Five Armies itself, and since the third movie has yet to be released we have no indication that he is or isn't going to be involved in that either. In the book the White Council had already assaulted Dol Guldur and driven him out before the Battle took place (this is obvious because Gandalf had returned in time for the Battle), so Sauron simply couldn't have been involved. But who knows what story the third movie is going to tell?

Answer 2

We don't know what else is going to be 'Jacksoned' in the third film, but in the books Sauron's northern army is stopped by Dain Ironfoot and King Brand. In 'The Quest of Erebor' (Unfinished Tales), Gandalf says

... with his far-stretched right hand Sauron could have done terrible harm in the North, while we defended Gondor, if King Brand and King Dain had not stood in his path. ... We might now only hope to return from the victory here to ruin and ash.

In this conversation, Gandalf is considering the possibility that the quest had never taken place or had failed, and Smaug had survived. However, I think the motivation works whatever happens to Smaug. Sauron didn't want Erebor and Dale to be reestablished; without them his northern army would face far less resistance.