What I have learned from studying counterfactual history is that the law of unintended consequences always kicks in no matter how secure you are in your plan. We have to live with the historical record as it is, like it or not.

What's interesting is that when you get into the post-war period, many of the narratives in books and movies conclude that if you killed Hitler, you're actually going to make history worse.

The first step to get people interested in history is to wonder how things could have been different.

Most people experience history as one damn fact after another in high school. But if you can wonder, "Wow, what if the US hadn't gotten involved in World War II?", you can become enthralled by the imaginary possibilities.

In times of uncertainty, we tend to move away from deterministic world views. And when we try to find moral footing for our actions, we compare ourselves to the foil of all foils, the Nazi period. It's a quest for moral certainty by saying, "Even if we're not doing great these days, at least we're not the Third Reich." Which can be consoling or alarmist. There's always a present-day agenda behind it.

Americans and British respondents don't want to let the German people off the hook. They make the case that if you get rid of Hitler, some other leader apart from Hitler would have emerged and, because of the structural constant of German nationalism, would have exploited German national feeling and produce the same kind of events no matter what.

What I have learned from studying counterfactual history is that the law of unintended consequences always kicks in no matter how secure you are in your plan. We have to live with the historical record as it is, like it or not.