I lived 70 years without even considering that, and I disagree with the idea that the Emerald City represents fiat currency or that the Wizard represents Jewish bankers, although it is true that there was a terrible financial crisis in 1893 which Baum no doubt remembered in 1899 when The Wonderful Wizard of Oz was published, and the whole book is about reality not being what people think it is. When confronted, the Wizard admits he's a humbug, but he solves the companions' problems like magic anyway--the solution was always in themselves, they just needed faith. The Wizard is willing to leave in shame, hardly the scheming cabal figure, but because of his essential honesty and helpfulness, all is eventually forgiven and he becomes the third most powerful magician in Oz. Glenda the Good is something of a deus ex machina in this and later books. Her story is never told, but time and again she tips the action toward success when everything looks hopeless. The Emerald City is a splendid construction but suffering a power vacuum because the rightful leader is gone, due to the machinations of various malevolent witches. There is eventually a little revolution led by Jinjur, no doubt inspired by the suffragettes. In fact, the villainy in Oz is rather more dominated by women than bankers. Finance is never a problem in Oz, where food grows on bushes, but even without food no one dies. There is no more money than there is sex. No one needs anything. The trouble makers in this world are wild animals, a very few essentially evil beings, mostly rogue witches. In two later books, the Gnomes appear, who might be a better analogy to bankers as they are fixated on precious gems and metals (but destroyed by eggs). Normally Oz is protected from them by the Deadly Desert, but like Uncle Scrooge's nemesis the Beagle Boys, the Gnomes plot constantly to conquer the Emerald City. They wouldn't do that if it was worthless fiat currency, it's the real deal. Basically Greed is the root evil in Oz.