You've got to fight the man, man. Well, at least when that man is a turtle that's super authoritarian and enjoys impinging on the rights and freedoms of his fellow turtles. It's clear from the very beginning of "Yertle the Turtle" that Yertle has a voracious appetite for power, and nothing is going to stop him from getting it. He wants to control not just that one turtle next to him, not just a stack of turtles, not just animals and objects that are very far away, but the entire universe.
Wanna know a little thing about power? If that's all you've got, it's a pretty shaky thing to stand on. And it usually topples. Just ask Hitler. And Yertle.
Q: Why is Yertle so mean to the other turtles?
A: Because he is Hitler—ahem, because he wants to feel better than everybody else like the King of the Playground.
Q: Why do the other turtles just do what Yertle says?
A: When someone is very powerful, saying no to them is scary. Is there anyone in your class you're scared of in this same kind of way?
Q: Why does Yertle get so angry at Mack?
A: Because Mack is kind of saying, "Hey, Yert! You ain't so powerful, and you don't deserve to be, so give it up." But Yertle doesn't want to give it up. Yertle wants more power.