Many people do not know that Taekwondo was at one time the official martial art of both the South and North Korean Militaries.
Fewer know that it had an effect on other early modern military martial arts programs – one example being, manual ST 31-204 which appears to have been for US Special Forces.
The greatest example of military Taekwondo is the famous Tiger Division.
This is a Taekwondo demonstration by South Korean Special Forces. Although many people appreciate that Taekwondo is a holistic development sport and has a great impact on physical, mental, and social skills, it is also very effective, when practiced as a martial art.
HERE is a good video about that.