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On N.S.I. and Its Founder–An Overview of an Uniquely American Martial Art

-By Michael Benjamin (NSI Full Instructor – Level 5)

“Kelly Worden is an icon of American martial arts.”

-Taky Kimura


There are few Grand Masters in history who have made as monumental and

varied an impact upon martial arts as the founder of Natural Spirit International

(NSI); namely, Kelly S. Worden, known respectfully and affectionately by we who

study and practice his way as The Datu. This is not some empty opinion or

boastful bravado alleged by one of his many thousands of students, but an

assertion easily proven by the simple historical and technical facts. The Datu’s

expertise exists in so many areas of martial specialty that his skill and knowledge

in the repertoire he has developed (known collectively as Natural Spirit)

represents a virtual encyclopedia of all major facets of hand-to-hand combat

pertinent to the modern martial practitioner.

Drawing from a plethora of sources gained in his half-century career of training

and teaching, what the Datu has developed as expressed in Natural Spirit reflects

a comprehensive dichotomy of the ancient-traditional synthesized with modern

progressive martial arts thus standing solely unique to other systems and styles

extant today. The Datu’s influences are well documented in many past sources,

but a brief perusal of his credentials easily asserts this point. From his humble

beginnings as a kid on the tough streets of Tacoma; to formal discipline in karate,

wrestling, boxing, and kickboxing; to his later pursuits of Arnis, Jeet Kune Do, and

Kuntao; to his development of the hand-to-hand combat system for the U.S.

Army’s First Special Forces Group; the creative synthesis that is now known as

Natural Spirit has evolved to be a premiere martial curriculum spanning the needs

of self-defense and hand-to-hand combat in such diverse areas as civilian, to

military, to law enforcement usage. So, what makes the Datu’s expression of

martial arts so special? Let us count the ways. . .


Prior to ever training with him in person, my first exposure to the Datu was in the

mid-1990’s. Back then I had been introduced by a friend to his first two knife

instructional tapes, along with the seminal videos “Destroy, Trap, Lock” and “The

Ultimate Street Fighter” from Paladin Press. At that time I had already been in

the martial arts for a decade, and had black belts in forms of Chinese Quanfa and

Okinawan Kempo. But seeing the Datu for the first time in these videos opened

my eyes to what I obviously did not know; to the lacking in my own arts and

deficiencies in my own abilities. I was amazed by his puma-like movement, by his

fluid streaming flow, by his creative tangents metaphorically reminiscent of a

Django Reinhardt jazz solo, and his acute teaching skill matching that of any

university professor.

I was also impressed by the balance he held in his character; a dichotomy of

justified ego, synthesized with a complete lack of pretentiousness. He was a

down-to-earth and real American, unlike many “masters” out there who tout all

credentials and lineage, but bluff with no substance. I knew this was a man with

immense knowledge to teach, and all these years later I am still scratching the

surface of his vast depths. He has proven to be one of those rare and selfless

teachers who not only leads, but serves his students. He gives of his knowledge

openly and thoroughly so that we who study his way can grow in a manner

consistent to the mission and standards of NSI.


The Datu, above all else, can be seen as one of the premier innovators in modern

martial arts. It is not only his emphasis on expressing an adaptable method of

self-defense equally workable for the Green Beret, to the Air Marshall, to the

housewife, but his focus on areas of study and training that makes him so unique.

As anyone who has studied his teaching can attest, there is no place within his

extensive curriculum where there is dross; no application that is not meant for

efficiency and effectiveness.

In his empty-handed method we see the basis of devastating striking sets honed

upon his training invention the Silent Fighter, and how this seamlessly merges

into the application of trapping, standing grappling, lock flow, base disruption,

and low level kicking. We see the best of boxing, kickboxing, JKD, and Kuntao

synthesized in these tactics.

Through the application of the concept of “translation” (taking such empty-

handed methods and applying them to weapons), a further level of the Datu’s

mastery is unveiled. It is perhaps in such weapons-based tactics that few have

excelled like the Datu. From the baton, to the blade, to the sibat, to his own

handload designs like the Travel Wrench, and even the Tomahawk, the Datu has

proven himself as a world class leader in weapons training with a focus on

weapons pertinent for the modern street and battlefield. It is no exaggeration to

say that many now famous instructors who espouse weapons credentials got

their training from him. And how many know the fact that a centuries old

Japanese Ninja clan literally sent their representative to America to get the Datu’s

knife training? How many teachers can legitimately make that claim?