I have walked seven miles per day in a nice residential neighborhood for three and a third years, 50 miles per week, 8,000 miles in 40 months. I have had two self defense cases. A flashlight would have been utterly useless to stop either of the two ambush attacks.
For more than a few months, I walked nights in my neighborhood with two X65s', one in each hand, enjoying the exhilaration of the combined beam performance. I do not do that anymore. When I walk at night, I carry only one light in one hand, and the other hand is empty, free to grab what I need to grab if I am ever ambush attacked again.
Lights are great for illuminating what you want to see. Successfully defending yourself against the hostility and/or evil of the surface of this earth necessitates other equipment.