The best part of this video is the assertion that slavery as an institution was the violence that instigated Harper's Ferry, rather than viewing the event as unprovoked violence, or as the "first shot" of the Civil War.
It's hard to argue that he was effective, I think.
Part of me wishes I could go back in time and give Nat Turner better weapons, if I'm being honest. Violence in service of ending slavery is and was justified.
I don't know, scaring the slavers so bad they made a whole regiment guard your execution sure sounds like you were effective at putting the fear of God into some sinners.