Faster than a speeding bullet. More powerful than a locomotive. Able to leap tall buildings in a single bound. It's Superman - strange visitor from another planet who came to Earth with powers and abilities far beyond those of mortal men. Superman - who can change the course of mighty rivers, bend steel with his bare hands, and who, disguised as Clark Kent, mild mannered reporter for a great metropolitan newspaper, fights the never ending battle for Truth, Justice and the American Way."
I want you to imagine for a moment that you have the powers of Superman, without necessarily having the angst, pressure, or desire to save the planet, maintain an alternate wardrobe, or figure out how to wear a cape without it bunching up inside your dress shirts. Don't even get me started on the whole red wedgie thing. So you're Clark Kent (or Ultra Woman), and someone just walked up to you, sticks a knife in your face, and says, "give me your lipstick?"
I was teaching a class once and a little child, about eight years old, was having a bad day. His problems started long before he arrived at class, and his classmates were not helping the situation at all. Kids can be oblivious and mean some times. So this little boy started pushing and shoving, and other kids started pushing back. I decided to use actions rather than words in this scenario, so I walked over to him and picked him up under my arm, like you might hold a laundry bag, carried him to the other side of the room and set him down as you might a tall plant.
I exaggerated the motion of 'planting' him down as if to reinforce this was now his spot. The whole action, from extraction, transportation, to plantation only took about ten seconds; and it provided the room of students, including Mr. Bad-Day with a little humor.
I provide these two scenarios to emphasize a particular point. Superman (Mr. Kent or Ms. Woman), would not need to blanch, duck, or execute a first-strike maneuver to defend himself against a knife-wielding attacker. Kal-El, as his friends call him, would simply remove the weapon from Mr. Not-a-good-day-to-play-the-lottery. Superman would have no fear of being hurt.
As I walked across the room to the young temper tot, I knew that neither he nor I were going to cause bodily harm. He was simply too small to inflict any injury on me, and I was too big to accidentally injure him. I was not afraid.
Fear is the cause of most fights. Fear of being hurt often causes someone to take the first swing. As a side note, the person who throws the first punch is rarely the aggressor - he's usually the one being aggressed. Why would this be? Fear. One person starts yelling and the other person's adrenalin starts pumping as fear causes the body to prepare for fight or flight. Modern culture says only chickens take flight (contrary to popular belief, chicks can fly), brave people stay for the fight.
So, once you are afraid in the face of a physical, violent confrontation, the natural reaction is to protect yourself with a physical response. Someone pushes you, pokes you in the chest angrily with their finger over and over, gets right in your face with ancestral admonishments, and your adrenaline seeps (gushes) into your system pushing out judgment and sanity. You respond with a well-deserved right cross - and the party has begun.
Now imagine that the push (remember the push?), never took place because you had the talent, reflexes, and timing to deflect the assailant's hands off to the side. When they wheeled around to try again you were equally evasive, or you were in a stance that utilized non-verbal communication to relay your total disinterest in humiliating this person in a crowded room. The same kind of disinterest that a great white has for your cute little Speedos.
Once your fear factor is removed, your actions become far less violent, confrontational, or physical. I've seen this play out in real life, in fact, I've seen it happen for me. Since I don't routinely frequent the local pubs so as to sneeze in the pints and quarts of total strangers, I'm not often asked to "step outside." But I have encountered a few lost souls who believed that since they have no idea who I am, I must be someone waiting and wanting to be assaulted. As of this writing, I have never had to perform an elbow strike, a back kick, a head butt (which just sounds wrong), or any other physical martial arts technique as a means of self defense.
I have however; been confronted angrily and found myself without fear. I knew that if it came to blows, Mr. Sadly-guessed-wrong would be having a really bad day. All humor and bravado aside, once you are able to control your fear, to maintain perspective in the face of physical or violent confrontation, you will find that the need to engage in fisticuffs is rare to almost the point of never.
As an aside, when someone says they are going to "put a world of hurt on you", it does not diffuse the situation to respond dryly "Not likely." In all of the 'this could turn ugly' conversations I've been in, I've been able to remain remain calm, stand my ground confidently, without the brash bravado sprinkled through this post and end the situation peacefully - enough.
Studying and practicing martial arts can give you control of your fear, along with great exercise, cardio stamina, and muscle tone.