"Nothing like that could ever happen again. Not in this day and age."

The Boy in the Striped Pajamas by John Boyne

"Bruno thought about his question, wanting to phrase it exactly right this time, just in case it came out as being rude or unco-operative.  'Who are all those people outside?' he said finally.

Father tilted his head to the left, looking a little confused by the question.  'Soldiers, Bruno,' he said.  'And secretaries.  Staff workers.  You've seen them all before, of course.'

'No, not them,' said Bruno.  'The people I see from my window.  In the huts, in the distance.  They're all dressed the same.'

'Ah, those people,' said Father, nodding his head and smiling slightly.  'Those people...well, they're not people at all, Bruno.'

Bruno frowned.  'They're not?' he asked, unsure what Father meant by that.

'Well, at least not as we understand the term,' Father continued.  'But you shouldn't be worrying about them right now.  They're nothing to do with you.  You have nothing whatsoever in common with them.  Just settle into your new home and be good, that's all I ask.  Accept the situation in which you find yourself and everything will be so much easier.'

'Yes, Father,' said Bruno, unsatisfied by the response.

He opened the door and Father called him back for a moment, standing up and raising an eyebrow as if he'd forgotten something.  Bruno remembered the moment his father made the signal, and said the phrase and imitated him exactly.  

He pushed his two feet together and shot his right arm into the air before clicking his two heels together and saying in as deep and clear a voice as possible--as much like Father's as he could manage--the words he said every time he left a soldier's presence.

'Heil Hitler,' he said, which, he presumed, was another way of saying, 'Well, goodbye for now, have a pleasant afternoon.' (52-54)