So, Hitler and the Nazis were right, then? They were justified in what they did? Or is the objection that they didn't limit their killing to secular Jews?
Maybe I'm wrong, but I took what was said in italics (reflecting Rabbi Lapin's argument) as commentary purely on a psychological level - as a study of culture, human beings, and their responses - not specific to any particular group of people. I don't believe anyone intended to say that Hitler was right to do what he did, but instead to offer commentary on human nature.
That's a mighty fine line to draw. Let me offer an analogy.
Suppose a woman goes to a bar and is sexually assaulted. Suppose that, after the fact, an observer comments that, well, she was dressed rather provocatively, and she probably shouldn't have been in that neighborhood anyway. At what point does this cross from a "study of human beings and their responses" to blaming the victim?