perhaps that cruelty was par for the course for most any invading/occupying war machine, while the holocaust was novel, in its sheer scale and industrial efficiency, so that's why people in germany blow off any other parts as just normal behaviour during wartime. all armies are perceived as more or less inhumane after all. no saints on the battlefield...

ethnic cleansing is as old as time, whereas the holocaust was organised genocide on an historically unsurpassed level.

'The history of public debt is full of irony. It rarely follows our ideas of order and justice.' Thomas Piketty