For the record:
The Wicked Witch of the West, as played by Hamilton, was Edgar Allan Woolf, Florence Ryerson and Noel Langley's creation based on the character created by L. Frank Baum for the 1900 book "The Wonderful Wizard of Oz"
Elphaba is Maguire's creation based on the character The Wicked Witch of the West created by Baum. She is also based, in part (largely appearance) on the character created by Woolf, Ryerson and Langley for the MGM motion picture classic "The Wizard of Oz"
Margaret Hamilton was not, despite what some people may attest, playing Elphaba.
Therefore, while she is the definitive Wicked Witch of the West (at least in mine and many people's books) she is not playing Elphaba in any sense of the character. Elphaba was a multi-faceted character (at least in Maguire's book), whereas the Wicked Witch (in the MGM motion picture) is merely a villian hell-bent on revenge. In the Baum novel she is merely a minor character that posed a threat to the Wizard and doesn't really pose much threat to Dorothy. Or a meatphor for the dust bowl, the threat of Dictatorship among other vauge skecthy political parallels.
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