The irony of truth
This novel is a brilliant examination of "imaginary" truth. Just because the toys don't literally come to life, that doesn't mean that Marie's imagination is meaningless and unimportant. Quite the contrary. Because she is imagining all the stories from scratch, we learn about her mind itself, and the way she makes sense of emotions through narrative. That ends up being a way more insightful truth than the literal truth of her stories. This irony is depicted in Drosselmeyer who takes what she says too literally and misses an opportunity to help her.
The dramatic irony of a thoughtful child
Marie's private thought life is depicted ironically, as if it were really happening. For the purposes of the story, the imaginary world might as well be real—it's real to the narrator and it's real to the little girl. This means that this book also contains a large amount of dramatic irony, because the young girl knows that each story is personally significant to her own emotional life, but everyone else assumes she is just playing. Her intimate thought life is too difficult to communicate, so she is left to work through her emotions privately.
The irony of time and youth
There is a paradoxical irony in the story. Because of the tragic deaths of her parents (we are left to assume from the situation), Marie is aware that bad things happen. How bad? Like, a child's parents dying. This leaves her permanently damaged and phobic about time, because the future is chaotic and unknown, and she's paranoid about tragedy striking again. Ironically, she herself is only a young child. She is a young character, afraid of aging, sickness, and death. In other words, she is ironic, because she has adult levels of experience, but only a child's mind to make sense of those emotions.
The irony of the clockwork world
The clockmaker loves his god-children, but he doesn't understand how to parent, and he has a hard time relating to them, but he makes them awesome Christmas gifts. He makes them a clockwork world where a bunch of interesting puppets come out on a sequence. The children are instantly obsessed with their gift, but ironically, it bores them quickly because it is too predictable. But, as they sit and stare at the clockwork world, their imaginations begin to create narrative out of the repetitive patterns, so maybe the clockmaker knew what he was doing after all.
The irony of warfare
One ironic aspect of this book's gruesome, horrifying warfare is that a child's imagination produced the story. Marie imagines a world that is as painful and violent as her real world, which is also ironic, given that she could have imagined a world where everyone was happy, but instead, she uses her imagination to work through real emotions that she doesn't understand. The irony of the war itself is simply that both sides have good reason to fight—both have been wronged by the other, but if they would forgive one another, they could be at peace. This is a classic Christmas idea because of Jesus's teachings against violence.
