The Wizard of Oz as an Allegory

So I was just quizzing my daughters tonight on the westward movement when it dawned on me that they are moving towards really understanding the allegory behind the Wizard of Oz.  Since I just did the post on the election of 1896 below and Keith hits on it in his video, here is the entire allegory.

• The Wizard of Oz is William McKinley who represents all politicians - full of hot air and not much action
• the Scarecrow who has no heart because he represented all farmers who were not rotating their crops and therefor depleting its nutrients - so hence no brain
• the Tin Man as he was emblematic of all factory owners who pushed children to work and had people at it six days a week and so they had no hearts and so it goes.  
• Just read the link above to get the full story.