The same intentness of focus that can produce bratty continuous demands for what they want, no matter what threats are administered, also allows them to persist in the right against the powerful. Children also have the protection of innocence, and even ignorance. The government of Orson Scott Card's Ender's Game uses children who think they are playing video games to save their world and destroy another. That they are being ruthlessly used and discarded adds another dimension to the story. Childish innocence includes a blithe sense of invulnerability, a lack of understanding that death is real and permanent and applies to them too.
Adults try to ward off evil with good sense.
We buy insurance. We wear our safety belts and take our vitamins. And if we were given Bilbo's ring and asked to fight a dragon, we would have many good and worthy reasons for staying safe at home. We have responsibilities. We have work to do, and children who depend on us.