Tactical German hand edge

If a toddler is indecent, misbehaves or naughty, her parents will smack her hand in the face, in good old Prussian fashion. Thus, the child is tactically immobilized.

John: "The motherfucker just won't be quiet! It doesn't help!"
Hans: "I know something. An old German educational method"
*Tactical German hand edge on child's face, causing child to magically calm down*