How does opening scene of Bruno and his friends represent their innocence?

In the opening scene, the boys are running free.... they're playing like any other children you would expect to see at that age. Unlike other children, they're playing soldiers..... people around them are being arrested. They're untouched, unmoved, and don't understand what they're seeing. Bruno's true innocence can be found in his lack of curiousity..... his complete disconnection from the world around him.