[Selmo]

I don't see The Mouth of Sauron as being "powerful" in the sense that Gandalf was powerful. He was a man, and , though twisted, he remained a man.

His power lies in his role as Sauron's messenger. He is obeyed because the orders he relays are Sauron's, not his own. I see him as a diplomat, negotiating with the nations to the East (was he the one Sauron sent to Erebor and Dale?).

From his reactions to Gandalf, I think that Gandalf's guess that The Mouth was expecting to become Sauron's regent in Gondor and Rohan was correct, so he must also have been an able administrator. Perhaps he was Sauron's Quartermaster-General, organising the housing, feeding and arming of the armies of Mordor, a task unsuited to orcs or Nazgul, orcs because of their limited inteligence and ill-discipline and the Nazgul being too valuable as weapons of war.
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