As soon as a developing self-defense situation is detected, a wise martial artist thinks about quickly removing himself or herself from the situation, says John Hackleman, a master of Hawaiian kempo. "If you can, talk your way out of it. Use verbal judo or de-escalation. Or get in your car and lock the door — that's the best-case scenario. If you have to, use stun and run.

"But you need to train for the worst-case scenario. If somebody punches you in the face for no reason, the de-escalation period is over. That's the scenario I'm interested in. I'll let the psychologists deal with everything else.

"Some instructors recommend trying to instill fear in an attacker, but Hackleman is not a fan of that tactic. "If he's on crack, there is no logic," he says. "And you could kick a person in the groin, and he could still manage to attack you. You've got to separate him from his consciousness."

Hackleman, who appeared on the cover of the December 2017/January 2018 issue of Black Belt, identifies several methods for achieving that goal. They include blunt-force trauma to the head from a strike or kick, interruption of the blood flow to the brain from a choke, and loss of blood as a result of a knife wound or gunshot."

When you've done one of these, then and only then are you safe," Hackleman says. "If you're an adult, this is what your training should focus on."