Nice video on the cause of the US Civil War, by the Head, Dept of History at US Military Academy, purposely wearing his dress blue uniform. Doubt it changes any minds however...
http://www.salon.com/2015/08/11/was_the_civil_war_fought_over_slavery_heres_the_video_to_show_idiots_who_think_the_answer_is_no/
A couple of my closest friends are junior instructors in the USMA history department and they have a ton of respect for COL Seidule. The original video was posted by Prager University and it's much less divisive ("idiots" in the title of the Salon article) and more intelligent than the Salon article would make it seem.
BTW, Prager has a good talk about the dropping of the atomic bomb on Hiroshima by a history professor at Notre Dame: https://www.facebook.com/prageru/videos (https://www.facebook.com/prageru/videos)
I was actually just out on a run with COL Seidule yesterday morning (with about 600 other people).