Your observation touches upon a crucial aspect of human psychology: the malleability of moral standards under certain conditions. Indeed, the human capacity to shift moral stands, sometimes under the influence of external pressures like state policy, propaganda, or societal norms, is a significant phenomenon. The Nazi regime adeptly manipulated these norms through the systematic dehumanization of certain groups, portraying them as lesser or subhuman. This facilitated a disturbing shift in societal moral values, making previously unthinkable acts seem justifiable or necessary. The state's role in this transformation was pivotal, as it not only propagated these ideas but also codified them into laws and regulations, thus normalizing and legalizing evil acts. Individuals found themselves in an environment where atrocious acts were not only legal but often rewarded, further entrenching these behaviors. This process underscores the dangerous power of dehumanization and the role of authoritative structures in shaping moral norms. It serves as a reminder of the need for constant vigilance and critical thinking in any society to prevent the erosion of universal human rights. Because there are situations when definitions of good and bad can be shifted, eroded, and manipulated. You can also say that many believed in what they were doing, but at some point they also got the understanding that the world around them - that begins to win the war - does not share this view and will hold them accountable of the crimes they perpetrated.