Catherine O’Donnell is an associate history professor at Arizona State University.

I am an historian with a secret. I don’t think studying the past tells us what to do in the present.

I should qualify that: If you are considering whether to invade Russia in winter, history provides the answer.

But I object when voices from across the political spectrum claim history tells us the answer to more complex questions: what our tax policy should be, why a specific crime happened and, most disturbingly, which political views prove us to be good citizens and which reveal us to be bad ones....