I am going to admit guilt in my oftentimes use of the two terms of self defense and self protection interchangeably.
  This admission of guilt notwithstanding, there is a subtle but vital difference in the meaning and implication of these two concepts, such that it could determine the outcome of a real-life street altercation to go in your favor or not.
  Self Defense Is Reactionary Let us first examine the more popular concept of self defense.
  If you are "defending" yourself, then you have allowed yourself to have been placed in a weaker and more compromising position.
  What I mean by this is that in the study of Reality-Based Fighting, you are trained first of all to have situational awareness which sharpens your perception to see an assault about to happen to you before it actually takes place.
  If you do not take the initiative and make the first and preemptive strike, then it is likely that you will allow the aggressor to launch the first strike.
  Now you are "reacting" and "defending" which is not  the place where you want to be.
Self Protection Is Proactive When you put yourself in the self protection mindset, you will not wait for someone to hit you or try to hit you.
  You will know that the fight started the minute that person laid eyes on you, started to yell obscenities at you and began to walk aggressive toward you into your personal space.
  The self protection mindset is to remove the danger before there is a chance for things to become worse.
  In the situation of an aggressor moving violently into your personal space with obvious intentions to do you bodily harm,  self protection dictates that you must now respond to that attack from an aggressive counter-offensive posture.
  What does this mean?  You strike first.
  You strike fast.
  You strike continuously -  until that threat is completely neutralized.