Ian Kershaw said this quote

“ The war was all that mattered to Hitler. Yet, cocooned in the strange world of the Wolf's Lair, he was increasingly severed from its realities, both at the front and at home. Detachment ruled out all vestiges of humanity. Even towards those in his own entourage who had been with him for many years, there was nothing resembling real affection, let alone friendship; genuine fondness was reserved only for his young Alsatian. He had described the human being the previous autumn as no more than 'a ridiculous cosmic bacterium (eine lächerliche Weltraumbakterie)'. Human life and suffering was, thus, of no consequence to him. He never visited a field-hospital, nor the homeless after bomb-raids. He saw no massacres, went near no concentration camp, viewed no compound of starving prisoners-of-war. His enemies were in his eyes like vermin to be stamped out. But his profound contempt for human existence extended to his own people. Decisions costing the lives of tens of thousands of his soldiers were made — perhaps it was only thus possible to make them — without consideration for any human plight. As he had told Guderian during the winter crisis, feelings of sympathy and pity for the suffering of his soldiers had to be shut out. For Hitler, the hundreds of thousands of dead and maimed were merely an abstraction, the suffering a necessary and justified sacrifice in the 'heroic struggle' for the survival of the people. ”