I read this book at 12 years old. It's extremely lengthy and boring. And the premise was wrong. There was not a single word criticizing Hitler and Nazism, let alone expose the horror of killing 6 million Jews. The entire book feels like Nazi propaganda. You'd feel sad because at the end "the third Reich" fell.
I didn't finish reading it because the rise and fall were both terrible to me.
Now I understand it's praising the rise and lamenting the fall of pure evil!