Well, really the question isn't concrete is it? First we have to understand what a Defense Art is. A defense art is anything which can be viably learned and used to effectively defend others. There are a number of skill sets that can be used from art forms to martial forms.
In the Star Wars fiction almost every Jedi knew martial arts. It has been defended that martial arts should be a primary practice among our real life counterparts,simply because it was practiced in the fiction. While I can certainly understand the usefulness of martial arts, there does seem to be a bit of a disconnect on the true value of it. In a world where it is not necessarily feasible to fight someone hand-to-hand,traditional martial arts seems to be nothing more than a teaching tool.
If you go around the Jedi Community and ask “Why is Martial Arts important to the Jedi Path?” you will get the same rhetoric. “It instills discipline”, “Inspires confidence”, “Good for physical fitness”, “Builds endurance”,“Allows you to protect others” and a number of other things. When it's broken down into the purpose of using martial arts, I find myself thinking “Okay, I know a woman which is a body builder and possesses all of those qualities, and she has never taken martial arts.”
I think that many of the people which cling to the martial arts as a requirement for being a Jedi miss the truth of things that we in the world are learning. They cling too much to this idea of one type of warrior. Today, when we look at warriors, we understand that the term has evolved. Even today, a knight does not necessarily refer to someone which is clad in iron ready for a sword fight against the enemy. Knights are symbolic of someone serving a greater cause. For the Jedi, it is in service to“the Force” or “the people” through the Jedi Code/Creed. We are also warriors, and we recognize that in order to be warriors we can use a number of different tools to accomplish this.
Sometimes through song:
What Would You Do- City High (a means of defending against prejudices and inspiring people to become better than they believe themselves to be)
Same Love- Macklemore (defending the LGBT community)
Black, White, Tan- Nicole C. Mullen(defending interracial relationships)
Sometimes they are in the form of art:
Harlem Renniassance (Civil Rights)
http://www.embryojesus.com(Catholic Pro-Life)
Satires (Whatever happens to be ofimportance to the audience)
It may come in the form of film:
Public Service Announcements
The Color Purple
Newscaster
You can find it being active with websites to raise awareness:
http://www.pacer.org/bullying/getinvolved/
Or in the form of physical combat:
Firearms
Traditional Martial Arts
Knife wielding
The list continues on, sometimes it takes creativity to find a method which you can use to defend others against something. If you latch onto the fiction, it is important to recognize that not all Jedi were charged with physically defending others. Some did so medically, through education and some through the art of diplomacy.
So the questions I ask you to think about are as follows:
What is it you want to protect?
What talents do you have?
And finally, how can you meld the two together?