Complex sentence: Hillgruber maintained that the slaughter of about 2.2 million defenceless men, women and children for the reasons of racist ideology cannot possibly be justified, and that those German generals who claimed that the "Einsatzgruppen" were a necessary anti-partisan response were lying.
Split into simpler sentences: Hillgruber maintained that the slaughter of about 2.2 million defenceless men, women and children for the reasons of racist ideology cannot be justified. Those German generals who claimed that the "Einsatzgruppen" were a necessary anti-partisan response were lying.