We have another new book on Hitler and the Holocaust, already hailed as a major contribution to our understanding of the root causes of the 20th century horrors which almost certainly have no parallel in civilized human history.

Prominent Yale historian Timothy Snyder’s new book – Black Earth: The Holocaust as History and Warning – indeed breaks new ground with regard to many aspects of Holocaust study. Particularly fascinating to us should be his insight concerning Hitler’s determination to rid the world of Jews. As Snyder expressed it in an interview just published in The Atlantic “There is in fact no way of thinking about the world, says Hitler, which allows us to see human beings as human beings. Any idea which allows us to see each other as human beings … come[s] from Jews.” As Snyder sees it, Hitler believed the only way for the world to revert to its natural order – that of brutal racial competition – was to eradicate the Jews.

I will leave to others a full review of the book as well as its many positive additions to our comprehension of an era so filled with warning lessons for global survival. What I do want to address is one particular aspect of Snyder’s approach which bears special relevance to the present age in which Jews are once again threatened with genocide by contemporary Hitlers, this time made more horrendous by the addition of nuclear capability.

In his treatment of the Holocaust, Snyder disagrees with the verdict of Emil Fackenheim that “There will never be an adequate explanation… The closer one gets to explicability the more one realizes nothing can make Hitler explicable,” and reveals what he considers a breakthrough of understanding about the man and the era famously called by Yehuda Bauer as “an eruption of demonism into history.”

Sadly, I believe Snyder falls victim to what Ron Rosenbaum some years ago strongly cautioned historians to avoid: Beware of explanations which project our own preconceptions and agendas. Indeed, the attempts to explain Hitler most often tell us more about ourselves our own self-images and our cultural predispositions than some indisputable truth about Hitler. The shapes we project onto the inky Rorschach of Hitler’s psyche are often cultural self-portraits in the negative.

What made Hitler the unparalleled satanic villain?

It is fascinating to note how “the explanation” varies in accord with cultural trends and pop psychology fashions. When low self-esteem was the focus of psychological scorn and educators kept harping on the need to praise children whatever their actions, it didn’t seem strange to have the popular reality TV series Unsolved Mysteries, in a highly praised episode, conclude that “The real explanation for Hitler turns out to be that terrifying contemporary plague of low self-esteem. He subjugated and killed millions because he could not overcome his feelings of inferiority.”

Not to be outdone, when dysfunctional families became pop culture’s enemy of the month, a spate of new books concluded that Hitler was the victim of a dysfunctional family with an overly stern father and an inability to establish a healthy relationship with his mother. Renowned Swiss psychoanalyst Alice Miller, in her book For Your Own Good, in seeking to advance her crusade against the evil of corporal punishment of children, strained to prove that adult Hitler’s evil can be traced to precisely this kind of punishment by his father.

Those more attuned to Freudian explanations for all of life’s choices preferred to focus on various sexual stories of Hitler’s youth to “explain” his demonic nature. Of the various possible reasons suggested, one that gained many adherents was the “Billy goat” theory – a genital deformity Hitler suffered as a result of an unfortunate encounter with a Billy goat which rendered him sexually incompetent and hence psychologically traumatized. Perhaps for the first time in history a Billy goat became a scapegoat – an explanation, like the others above, which share a profoundly disturbing conclusion: Hitler too must be understood as a victim, a victim of Freudian drives beyond his control, a victim of family relationships for which he was not responsible.

And here lies the most terrible sin of all in these varied attempts to define Hitler’s evil. To explain is to begin to excuse – to exculpate. To displace guilt from Hitler to the seemingly rational cause. To offer reason for the unreasonable. A step down the path to Spinoza’s famous maxim that “To understand all is to forgive all.”

So let us come now to Snyder’s explanation. Perhaps it should come as no surprise that when global warming has become the contemporary mantra and ecology a major concern of our times, a historian’s hindsight finds it reasonable to attribute the Holocaust to “ecological anti-Semitism.” Hitler was concerned with the very same problem that now engages us. He was motivated by the necessity for lebensraum, or “living space”, for the German race. The Ukraine and Eastern Europe presented the only solution for an intractable problem: The crisis of insufficient land for a growing population which ecologically could not be fed required conquest of its neighbors and genocide of a specific segment of the population whose values stood in the way of his goals.

It is a 21st century explanation for a 20th century crime beyond parallel. It may well have a measure of truth – no better or worse than the theories of Hitler as a victim of bad parenting or casualty of a mental disease, dysfunction, or syndrome, Hitler as madman, psychopath, demented, terminally insane – all of which tend to exculpate if not excuse the crimes he perpetrated. What it ignores is the simple reality of pure and unadulterated evil.

Milton Himmelfarb was right. In his famous essay, No Hitler, No Holocaust, he wrote: “Hitler murdered the Jews not because he had to, not because he was impelled by abstract historical forces toward an inevitable end, but because of his own personal will and desire, because he wanted to.” Evil exists in this world. Evil people commit despicable acts. Evil trumps reason. Evil is not deterred by reason. To put it bluntly, evil by definition is irrational.

Hitler was not rational; he was evil. And so too are contemporary Hamans who openly proclaim genocide as their goal.

It is a truth we desperately need to grasp for the present-day Hitlers as well. In defending the nuclear deal with Iran, President Obama told The Atlantic’s Jeffrey Goldberg, “I think Iranian supreme leader Ayatollah Ali Khamenei’s ideology is steeped with anti-Semitism, and if he could, without catastrophic costs, inflict great harm on Israel, I am confident that he would. But it is possible for leaders or regimes to be cruel, bigoted, twisted in their worldviews and still make rational calculations with respect to their limits and their self-preservation.”

It is possible. But Hitler didn’t – and that needs to be remembered. Hitler was not rational; he was evil. And so too are contemporary Hamans who openly proclaim genocide as their goal.

Instead of rationalizing evil we must remember that evil is far more powerfully attracted to greater evil than it is to reason.