There is much useful discussion on the internet of the motivations, rationality, or intentions of the Germans who participated in or planned the Holocaust. Much of this is off the mark, and perhaps I can clarify in what way.

Understanding the intentions of another person is very difficult. It is a black box that often we cannot penetrate, even for our loved ones. Even simple cases can mislead us. Say I get up from my computer, go to the refrigerator, take out ice water, pour it into a glass, and drink it. What was my intention? To satisfy my thirst seems obvious. But, it may be I had an itch in my throat and was trying to eliminate it. Or, I read that I'm supposed to drink three glasses of water a day, and though I wasn't thirsty, I was trying to fulfil the quota. Or, I thought the water tasted odd this morning, and was just testing it this afternoon. And so on.

When intentions or so opaque, how do we deal with them? One way is to try to understand why a person does what they do. We try to get inside their head, see things as they do, look at the circumstances of their actions, see how they have behaved formerly, view what they have said about their actions, and so on. This has been the usual approach to assessing motives in the Holocaust. In effect, this treats a person's intentions as part of their life path, which includes sayings, behavior, and associated conditions. "Sweetheart," my wife says, "I'm going to the store" How do I know this is her intention? From my total knowledge of her. Also, she has gone out to play tennis with her friends and is an hour late returning. How do I know her intentions-why she is late? From past experience, I understand that she has probably gone shopping.

Similarly, people have tried to understand (verstehen) the Holocaust as due to, for example, believing the Jews are vermin, sheer hatred of the Jew, psychological projection and displacement, German submission to authority, economic considerations, and so on. I have no quarrel with any of this, and no doubt, readers will understand the Holocaust depending on their own unique experience and beliefs.

But, if one's purpose is to prevent genocide or mass murder generally, understanding the Holocaust in this way is not enough, not if one wants to know as well why Jews were murdered in historic times by the Poles, Rumanians, Hungarians, Croatians, Ukrainians, Russians, etc. Nor are these understandings of the Holocaust sufficient if one also wants to know why the Rwandan rulers planned from the top to murder up to a million Tutsi; the Young Turks murdered en mass their Armenians; the Pakistan military did similarly to their East Pakistan Bengalis and Hindus; the Khmer Rouge did this to their Buddhists, Chams, and Vietnamese-Cambodians; and so on, and on, then we need an explanation.

Explanation provides the basis for predicting a behavior will occur. Understanding helps form an explanation, but also may inhibit it. That is, understanding that the Nazis characterized the Jews as vermin that they were eradicating, which is a fact, does not help in predicting genocide elsewhere, however. For example, had you looked for something like this view by top leaders as a predictor of genocide, you would not have predicted any of other major genocides in the 20th Century. Even the presence of something like this view would not have predicted genocide. I believe it is fair to say that some French and Polish political and military leaders held this view, and yet did not try to promote a large-scale genocide of their Jews.

Many sociologists and political scientists have been searching for an explanation of genocide and mass murder that would give us a warning of when it might happen. The problem has been that what seems predictive via understanding in one national/cultural context has not been in another. Accordingly, some of us have taken a different approach. Can we find a condition x, such that its presence or absence makes it more likely for the situationally unique factors given by our understanding of a people to cause genocide and mass murder? We have studied many such possible predisposing conditions, such as education, ethnic/racial diversity, population density, religion, ethnicity or race, regional location, and culture. For example, is genocide more likely when there are many ethnic groups in a country and when one particular ethnic group dominates others? The answer is no, not generally.

But, one condition does stand out in all such research, and that is the kind of political system that a nation has, and particularly, the power at the center. Virtually all genocides and nongenocidal mass murders obey the following social law. The more power those who rule have, the less the human rights and civil liberties of their people, then the more likely the rulers will commit genocide and mass murder. Democracies commit the least such murder of their citizens; totalitarian regimes the most. Power kills, absolute power kills absolutely.

This is the explanation of the Holocaust and almost all genocides. It says that when any regime, as did that of the Nazis, can command their subjects as they wish, then those unique elements, such as hatred, economic envy, threats to power, etc., can have their lethal effects. So understanding does have a crucial role. It provides insight into why, given authoritarian or totalitarian rule, something like the Holocaust can occur. But, alone this understanding will not provide much help to prevent it or other genocides.

The explanation in terms of power does, however. Therefore, how do we try to assure "Never again"? Foster liberal democratic freedom-reduce power at the center.

Note that throughout democratic Europe, including Germany, Rumania, Hungary, Russia, and Ukraine, any repeat of any mass murder of Jews, is now inconceivable. So it will be as long as these countries remain democratic.